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<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="math_toolkit.constants"></a><a class="link" href="constants.html" title="The Mathematical Constants">The Mathematical Constants</a>
</h2></div></div></div>
<p>
      This section lists the mathematical constants, their use(s) (and sometimes
      rationale for their inclusion).
    </p>
<div class="table">
<a name="math_toolkit.constants.mathematical_constants"></a><p class="title"><b>Table&#160;4.1.&#160;Mathematical Constants</b></p>
<div class="table-contents"><table class="table" summary="Mathematical Constants">
<colgroup>
<col>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
              <p>
                name
              </p>
            </th>
<th>
              <p>
                formula
              </p>
            </th>
<th>
              <p>
                Value (6 decimals)
              </p>
            </th>
<th>
              <p>
                Uses and Rationale
              </p>
            </th>
</tr></thead>
<tbody>
<tr>
<td>
              <p>
                <span class="bold"><strong>Rational fractions</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                half
              </p>
            </td>
<td>
              <p>
                1/2
              </p>
            </td>
<td>
              <p>
                0.5
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                third
              </p>
            </td>
<td>
              <p>
                1/3
              </p>
            </td>
<td>
              <p>
                0.333333
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                two_thirds
              </p>
            </td>
<td>
              <p>
                2/3
              </p>
            </td>
<td>
              <p>
                0.66667
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                three_quarters
              </p>
            </td>
<td>
              <p>
                3/4
              </p>
            </td>
<td>
              <p>
                0.75
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>two and related</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                root_two
              </p>
            </td>
<td>
              <p>
                &#8730;2
              </p>
            </td>
<td>
              <p>
                1.41421
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                root_three
              </p>
            </td>
<td>
              <p>
                &#8730;3
              </p>
            </td>
<td>
              <p>
                1.73205
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                half_root_two
              </p>
            </td>
<td>
              <p>
                &#8730;2 /2
              </p>
            </td>
<td>
              <p>
                0.707106
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                ln_two
              </p>
            </td>
<td>
              <p>
                ln(2)
              </p>
            </td>
<td>
              <p>
                0.693147
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                ln_ten
              </p>
            </td>
<td>
              <p>
                ln(10)
              </p>
            </td>
<td>
              <p>
                2.30258
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                ln_ln_two
              </p>
            </td>
<td>
              <p>
                ln(ln(2))
              </p>
            </td>
<td>
              <p>
                -0.366512
              </p>
            </td>
<td>
              <p>
                Gumbel distribution median
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                root_ln_four
              </p>
            </td>
<td>
              <p>
                &#8730;ln(4)
              </p>
            </td>
<td>
              <p>
                1.177410
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_root_two
              </p>
            </td>
<td>
              <p>
                1/&#8730;2
              </p>
            </td>
<td>
              <p>
                0.707106
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>&#960; and related</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi
              </p>
            </td>
<td>
              <p>
                pi
              </p>
            </td>
<td>
              <p>
                3.14159
              </p>
            </td>
<td>
              <p>
                Ubiquitous. Archimedes constant <a href="http://en.wikipedia.org/wiki/Pi" target="_top">&#960;</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                half_pi
              </p>
            </td>
<td>
              <p>
                &#960;/2
              </p>
            </td>
<td>
              <p>
                1.570796
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                third_pi
              </p>
            </td>
<td>
              <p>
                &#960;/3
              </p>
            </td>
<td>
              <p>
                1.04719
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                sixth_pi
              </p>
            </td>
<td>
              <p>
                &#960;/6
              </p>
            </td>
<td>
              <p>
                0.523598
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                two_pi
              </p>
            </td>
<td>
              <p>
                2&#960;
              </p>
            </td>
<td>
              <p>
                6.28318
              </p>
            </td>
<td>
              <p>
                Many uses, most simply, circumference of a circle
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                two_thirds_pi
              </p>
            </td>
<td>
              <p>
                2/3 &#960;
              </p>
            </td>
<td>
              <p>
                2.09439
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Sphere#Volume_of_a_sphere" target="_top">volume
                of a hemi-sphere</a> = 4/3 &#960; r&#179;
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                three_quarters_pi
              </p>
            </td>
<td>
              <p>
                3/4 &#960;
              </p>
            </td>
<td>
              <p>
                2.35619
              </p>
            </td>
<td>
              <p>
                = 3/4 &#960;
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                four_thirds_pi
              </p>
            </td>
<td>
              <p>
                4/3 &#960;
              </p>
            </td>
<td>
              <p>
                4.18879
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Sphere#Volume_of_a_sphere" target="_top">volume
                of a sphere</a> = 4/3 &#960; r&#179;
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_two_pi
              </p>
            </td>
<td>
              <p>
                1/(2&#960;)
              </p>
            </td>
<td>
              <p>
                1.59155
              </p>
            </td>
<td>
              <p>
                Widely used
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                root_pi
              </p>
            </td>
<td>
              <p>
                &#8730;&#960;
              </p>
            </td>
<td>
              <p>
                1.77245
              </p>
            </td>
<td>
              <p>
                Widely used
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                root_half_pi
              </p>
            </td>
<td>
              <p>
                &#8730; &#960;/2
              </p>
            </td>
<td>
              <p>
                1.25331
              </p>
            </td>
<td>
              <p>
                Widely used
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                root_two_pi
              </p>
            </td>
<td>
              <p>
                &#8730; &#960;*2
              </p>
            </td>
<td>
              <p>
                2.50662
              </p>
            </td>
<td>
              <p>
                Widely used
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_root_pi
              </p>
            </td>
<td>
              <p>
                1/&#8730;&#960;
              </p>
            </td>
<td>
              <p>
                0.564189
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_root_two_pi
              </p>
            </td>
<td>
              <p>
                1/&#8730;(2&#960;)
              </p>
            </td>
<td>
              <p>
                0.398942
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                root_one_div_pi
              </p>
            </td>
<td>
              <p>
                &#8730;(1/&#960;
              </p>
            </td>
<td>
              <p>
                0.564189
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi_minus_three
              </p>
            </td>
<td>
              <p>
                &#960;-3
              </p>
            </td>
<td>
              <p>
                0.141593
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                four_minus_pi
              </p>
            </td>
<td>
              <p>
                4 -&#960;
              </p>
            </td>
<td>
              <p>
                0.858407
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi_pow_e
              </p>
            </td>
<td>
              <p>
                &#960;<sup>e</sup>
              </p>
            </td>
<td>
              <p>
                22.4591
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi_sqr
              </p>
            </td>
<td>
              <p>
                &#960;<sup>2</sup>
              </p>
            </td>
<td>
              <p>
                9.86960
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi_sqr_div_six
              </p>
            </td>
<td>
              <p>
                &#960;<sup>2</sup>/6
              </p>
            </td>
<td>
              <p>
                1.64493
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                pi_cubed
              </p>
            </td>
<td>
              <p>
                &#960;<sup>3</sup>
              </p>
            </td>
<td>
              <p>
                31.00627
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                cbrt_pi
              </p>
            </td>
<td>
              <p>
                &#8730;<sup>3</sup> &#960;
              </p>
            </td>
<td>
              <p>
                1.46459
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_cbrt_pi
              </p>
            </td>
<td>
              <p>
                1/&#8730;<sup>3</sup> &#960;
              </p>
            </td>
<td>
              <p>
                0.682784
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>Euler's e and related</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                e
              </p>
            </td>
<td>
              <p>
                e
              </p>
            </td>
<td>
              <p>
                2.71828
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/E_(mathematical_constant)" target="_top">Euler's
                constant e</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                exp_minus_half
              </p>
            </td>
<td>
              <p>
                e <sup>-1/2</sup>
              </p>
            </td>
<td>
              <p>
                0.606530
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                e_pow_pi
              </p>
            </td>
<td>
              <p>
                e <sup>&#960;</sup>
              </p>
            </td>
<td>
              <p>
                23.14069
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                root_e
              </p>
            </td>
<td>
              <p>
                &#8730; e
              </p>
            </td>
<td>
              <p>
                1.64872
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                log10_e
              </p>
            </td>
<td>
              <p>
                log10(e)
              </p>
            </td>
<td>
              <p>
                0.434294
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_log10_e
              </p>
            </td>
<td>
              <p>
                1/log10(e)
              </p>
            </td>
<td>
              <p>
                2.30258
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>Trigonometric</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                degree
              </p>
            </td>
<td>
              <p>
                radians = &#960; / 180
              </p>
            </td>
<td>
              <p>
                0.017453
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                radian
              </p>
            </td>
<td>
              <p>
                degrees = 180 / &#960;
              </p>
            </td>
<td>
              <p>
                57.2957
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                sin_one
              </p>
            </td>
<td>
              <p>
                sin(1)
              </p>
            </td>
<td>
              <p>
                0.841470
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                cos_one
              </p>
            </td>
<td>
              <p>
                cos(1)
              </p>
            </td>
<td>
              <p>
                0.54030
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                sinh_one
              </p>
            </td>
<td>
              <p>
                sinh(1)
              </p>
            </td>
<td>
              <p>
                1.17520
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                cosh_one
              </p>
            </td>
<td>
              <p>
                cosh(1)
              </p>
            </td>
<td>
              <p>
                1.54308
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>Phi</strong></span>
              </p>
            </td>
<td>
              <p>
                Phidias golden ratio
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Golden_ratio" target="_top">Phidias golden
                ratio</a>
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                phi
              </p>
            </td>
<td>
              <p>
                (1 + &#8730;5) /2
              </p>
            </td>
<td>
              <p>
                1.61803
              </p>
            </td>
<td>
              <p>
                finance
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                ln_phi
              </p>
            </td>
<td>
              <p>
                ln(&#966;)
              </p>
            </td>
<td>
              <p>
                0.48121
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_ln_phi
              </p>
            </td>
<td>
              <p>
                1/ln(&#966;)
              </p>
            </td>
<td>
              <p>
                2.07808
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>Euler's Gamma</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                euler
              </p>
            </td>
<td>
              <p>
                euler
              </p>
            </td>
<td>
              <p>
                0.577215
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Euler%E2%80%93Mascheroni_constant" target="_top">Euler-Mascheroni
                gamma constant</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                one_div_euler
              </p>
            </td>
<td>
              <p>
                1/euler
              </p>
            </td>
<td>
              <p>
                1.73245
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                euler_sqr
              </p>
            </td>
<td>
              <p>
                euler<sup>2</sup>
              </p>
            </td>
<td>
              <p>
                0.333177
              </p>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                <span class="bold"><strong>Misc</strong></span>
              </p>
            </td>
<td>
            </td>
<td>
            </td>
<td>
            </td>
</tr>
<tr>
<td>
              <p>
                zeta_two
              </p>
            </td>
<td>
              <p>
                &#950;(2)
              </p>
            </td>
<td>
              <p>
                1.64493
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Riemann_zeta_function" target="_top">Riemann
                zeta function</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                zeta_three
              </p>
            </td>
<td>
              <p>
                &#950;(3)
              </p>
            </td>
<td>
              <p>
                1.20205
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Riemann_zeta_function" target="_top">Riemann
                zeta function</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                catalan
              </p>
            </td>
<td>
              <p>
                <span class="emphasis"><em>K</em></span>
              </p>
            </td>
<td>
              <p>
                0.915965
              </p>
            </td>
<td>
              <p>
                <a href="http://mathworld.wolfram.com/CatalansConstant.html" target="_top">Catalan
                (or Glaisher) combinatorial constant</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                glaisher
              </p>
            </td>
<td>
              <p>
                <span class="emphasis"><em>A</em></span>
              </p>
            </td>
<td>
              <p>
                1.28242
              </p>
            </td>
<td>
              <p>
                <a href="https://oeis.org/A074962/constant" target="_top">Decimal expansion
                of Glaisher-Kinkelin constant</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                khinchin
              </p>
            </td>
<td>
              <p>
                <span class="emphasis"><em>k</em></span>
              </p>
            </td>
<td>
              <p>
                2.685452
              </p>
            </td>
<td>
              <p>
                <a href="https://oeis.org/A002210/constant" target="_top">Decimal expansion
                of Khinchin constant</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                extreme_value_skewness
              </p>
            </td>
<td>
              <p>
                12&#8730;6 &#950;(3)/ &#960;<sup>3</sup>
              </p>
            </td>
<td>
              <p>
                1.139547
              </p>
            </td>
<td>
              <p>
                Extreme value distribution
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                rayleigh_skewness
              </p>
            </td>
<td>
              <p>
                2&#8730;&#960;(&#960;-3)/(4 - &#960;)<sup>3/2</sup>
              </p>
            </td>
<td>
              <p>
                0.631110
              </p>
            </td>
<td>
              <p>
                Rayleigh distribution skewness
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                rayleigh_kurtosis_excess
              </p>
            </td>
<td>
              <p>
                -(6&#960;<sup>2</sup>-24&#960;+16)/(4-&#960;)<sup>2</sup>
              </p>
            </td>
<td>
              <p>
                0.245089
              </p>
            </td>
<td>
              <p>
                <a href="http://en.wikipedia.org/wiki/Rayleigh_distribution" target="_top">Rayleigh
                distribution kurtosis excess</a>
              </p>
            </td>
</tr>
<tr>
<td>
              <p>
                rayleigh_kurtosis
              </p>
            </td>
<td>
              <p>
                3+(6&#960;<sup>2</sup>-24&#960;+16)/(4-&#960;)<sup>2</sup>
              </p>
            </td>
<td>
              <p>
                3.245089
              </p>
            </td>
<td>
              <p>
                Rayleigh distribution kurtosis
              </p>
            </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><div class="note"><table border="0" summary="Note">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../doc/src/images/note.png"></td>
<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
        Integer values are <span class="bold"><strong>not included</strong></span> in this
        list of math constants, however interesting, because they can be so easily
        and exactly constructed, even for UDT, for example: <code class="computeroutput"><span class="keyword">static_cast</span><span class="special">&lt;</span><span class="identifier">cpp_float</span><span class="special">&gt;(</span><span class="number">42</span><span class="special">)</span></code>.
      </p></td></tr>
</table></div>
<div class="tip"><table border="0" summary="Tip">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
<th align="left">Tip</th>
</tr>
<tr><td align="left" valign="top"><p>
        If you know the approximate value of the constant, you can search for the
        value to find Boost.Math chosen name in this table.
      </p></td></tr>
</table></div>
<div class="tip"><table border="0" summary="Tip">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
<th align="left">Tip</th>
</tr>
<tr><td align="left" valign="top"><p>
        Bernoulli numbers are available at <a class="link" href="number_series/bernoulli_numbers.html" title="Bernoulli Numbers">Bernoulli
        numbers</a>.
      </p></td></tr>
</table></div>
<div class="tip"><table border="0" summary="Tip">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
<th align="left">Tip</th>
</tr>
<tr><td align="left" valign="top"><p>
        Factorials are available at <a class="link" href="factorials/sf_factorial.html" title="Factorial">factorial</a>.
      </p></td></tr>
</table></div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright &#169; 2006-2010, 2012-2014 Nikhar Agrawal,
      Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos, Hubert
      Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Johan R&#229;de, Gautam Sewani,
      Benjamin Sobotta, Thijs van den Berg, Daryle Walker and Xiaogang Zhang<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
</div></td>
</tr></table>
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	22	<div class="spirit-nav">
	23	<a accesskey="p" href="tutorial/user_def.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../constants.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="new_const.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
	24	</div>
	25	<div class="section">
	26	<div class="titlepage"><div><div><h2 class="title" style="clear: both">
	27	<a name="math_toolkit.constants"></a><a class="link" href="constants.html" title="The Mathematical Constants">The Mathematical Constants</a>
	28	</h2></div></div></div>
	29	<p>
	30	This section lists the mathematical constants, their use(s) (and sometimes
	31	rationale for their inclusion).
	32	</p>
	33	<div class="table">
	34	<a name="math_toolkit.constants.mathematical_constants"></a><p class="title"><b>Table 4.1. Mathematical Constants</b></p>
	35	<div class="table-contents"><table class="table" summary="Mathematical Constants">
	36	<colgroup>
	37	<col>
	38	<col>
	39	<col>
	40	<col>
	41	</colgroup>
	42	<thead><tr>
	43	<th>
	44	<p>
	45	name
	46	</p>
	47	</th>
	48	<th>
	49	<p>
	50	formula
	51	</p>
	52	</th>
	53	<th>
	54	<p>
	55	Value (6 decimals)
	56	</p>
	57	</th>
	58	<th>
	59	<p>
	60	Uses and Rationale
	61	</p>
	62	</th>
	63	</tr></thead>
	64	<tbody>
65	<tr>
66	<td>
67	<p>
68	<span class="bold"><strong>Rational fractions</strong></span>
69	</p>
70	</td>
71	<td>
72	</td>
73	<td>
74	</td>
75	<td>
76	</td>
77	</tr>
78	<tr>
79	<td>
80	<p>
81	half
82	</p>
83	</td>
84	<td>
85	<p>
86	1/2
87	</p>
88	</td>
89	<td>
90	<p>
91	0.5
92	</p>
93	</td>
94	<td>
95	</td>
96	</tr>
97	<tr>
98	<td>
99	<p>
100	third
101	</p>
102	</td>
103	<td>
104	<p>
105	1/3
106	</p>
107	</td>
108	<td>
109	<p>
110	0.333333
111	</p>
112	</td>
113	<td>
114	</td>
115	</tr>
116	<tr>
117	<td>
118	<p>
119	two_thirds
120	</p>
121	</td>
122	<td>
123	<p>
124	2/3
125	</p>
126	</td>
127	<td>
128	<p>
129	0.66667
130	</p>
131	</td>
132	<td>
133	</td>
134	</tr>
135	<tr>
136	<td>
137	<p>
138	three_quarters
139	</p>
140	</td>
141	<td>
142	<p>
143	3/4
144	</p>
145	</td>
146	<td>
147	<p>
148	0.75
149	</p>
150	</td>
151	<td>
152	</td>
153	</tr>
154	<tr>
155	<td>
156	<p>
157	<span class="bold"><strong>two and related</strong></span>
158	</p>
159	</td>
160	<td>
161	</td>
162	<td>
163	</td>
164	<td>
165	</td>
166	</tr>
167	<tr>
168	<td>
169	<p>
170	root_two
171	</p>
172	</td>
173	<td>
174	<p>
175	√2
176	</p>
177	</td>
178	<td>
179	<p>
180	1.41421
181	</p>
182	</td>
183	<td>
184	</td>
185	</tr>
186	<tr>
187	<td>
188	<p>
189	root_three
190	</p>
191	</td>
192	<td>
193	<p>
194	√3
195	</p>
196	</td>
197	<td>
198	<p>
199	1.73205
200	</p>
201	</td>
202	<td>
203	</td>
204	</tr>
205	<tr>
206	<td>
207	<p>
208	half_root_two
209	</p>
210	</td>
211	<td>
212	<p>
213	√2 /2
214	</p>
215	</td>
216	<td>
217	<p>
218	0.707106
219	</p>
220	</td>
221	<td>
222	</td>
223	</tr>
224	<tr>
225	<td>
226	<p>
227	ln_two
228	</p>
229	</td>
230	<td>
231	<p>
232	ln(2)
233	</p>
234	</td>
235	<td>
236	<p>
237	0.693147
238	</p>
239	</td>
240	<td>
241	</td>
242	</tr>
243	<tr>
244	<td>
245	<p>
246	ln_ten
247	</p>
248	</td>
249	<td>
250	<p>
251	ln(10)
252	</p>
253	</td>
254	<td>
255	<p>
256	2.30258
257	</p>
258	</td>
259	<td>
260	</td>
261	</tr>
262	<tr>
263	<td>
264	<p>
265	ln_ln_two
266	</p>
267	</td>
268	<td>
269	<p>
270	ln(ln(2))
271	</p>
272	</td>
273	<td>
274	<p>
275	-0.366512
276	</p>
277	</td>
278	<td>
279	<p>
280	Gumbel distribution median
281	</p>
282	</td>
283	</tr>
284	<tr>
285	<td>
286	<p>
287	root_ln_four
288	</p>
289	</td>
290	<td>
291	<p>
292	√ln(4)
293	</p>
294	</td>
295	<td>
296	<p>
297	1.177410
298	</p>
299	</td>
300	<td>
301	</td>
302	</tr>
303	<tr>
304	<td>
305	<p>
306	one_div_root_two
307	</p>
308	</td>
309	<td>
310	<p>
311	1/√2
312	</p>
313	</td>
314	<td>
315	<p>
316	0.707106
317	</p>
318	</td>
319	<td>
320	</td>
321	</tr>
322	<tr>
323	<td>
324	<p>
325	<span class="bold"><strong>π and related</strong></span>
326	</p>
327	</td>
328	<td>
329	</td>
330	<td>
331	</td>
332	<td>
333	</td>
334	</tr>
335	<tr>
336	<td>
337	<p>
338	pi
339	</p>
340	</td>
341	<td>
342	<p>
343	pi
344	</p>
345	</td>
346	<td>
347	<p>
348	3.14159
349	</p>
350	</td>
351	<td>
352	<p>
353	Ubiquitous. Archimedes constant <a href="http://en.wikipedia.org/wiki/Pi" target="_top">π</a>
354	</p>
355	</td>
356	</tr>
357	<tr>
358	<td>
359	<p>
360	half_pi
361	</p>
362	</td>
363	<td>
364	<p>
365	π/2
366	</p>
367	</td>
368	<td>
369	<p>
370	1.570796
371	</p>
372	</td>
373	<td>
374	</td>
375	</tr>
376	<tr>
377	<td>
378	<p>
379	third_pi
380	</p>
381	</td>
382	<td>
383	<p>
384	π/3
385	</p>
386	</td>
387	<td>
388	<p>
389	1.04719
390	</p>
391	</td>
392	<td>
393	</td>
394	</tr>
395	<tr>
396	<td>
397	<p>
398	sixth_pi
399	</p>
400	</td>
401	<td>
402	<p>
403	π/6
404	</p>
405	</td>
406	<td>
407	<p>
408	0.523598
409	</p>
410	</td>
411	<td>
412	</td>
413	</tr>
414	<tr>
415	<td>
416	<p>
417	two_pi
418	</p>
419	</td>
420	<td>
421	<p>
422	2π
423	</p>
424	</td>
425	<td>
426	<p>
427	6.28318
428	</p>
429	</td>
430	<td>
431	<p>
432	Many uses, most simply, circumference of a circle
433	</p>
434	</td>
435	</tr>
436	<tr>
437	<td>
438	<p>
439	two_thirds_pi
440	</p>
441	</td>
442	<td>
443	<p>
444	2/3 π
445	</p>
446	</td>
447	<td>
448	<p>
449	2.09439
450	</p>
451	</td>
452	<td>
453	<p>
454	<a href="http://en.wikipedia.org/wiki/Sphere#Volume_of_a_sphere" target="_top">volume
455	of a hemi-sphere</a> = 4/3 π r³
456	</p>
457	</td>
458	</tr>
459	<tr>
460	<td>
461	<p>
462	three_quarters_pi
463	</p>
464	</td>
465	<td>
466	<p>
467	3/4 π
468	</p>
469	</td>
470	<td>
471	<p>
472	2.35619
473	</p>
474	</td>
475	<td>
476	<p>
477	= 3/4 π
478	</p>
479	</td>
480	</tr>
481	<tr>
482	<td>
483	<p>
484	four_thirds_pi
485	</p>
486	</td>
487	<td>
488	<p>
489	4/3 π
490	</p>
491	</td>
492	<td>
493	<p>
494	4.18879
495	</p>
496	</td>
497	<td>
498	<p>
499	<a href="http://en.wikipedia.org/wiki/Sphere#Volume_of_a_sphere" target="_top">volume
500	of a sphere</a> = 4/3 π r³
501	</p>
502	</td>
503	</tr>
504	<tr>
505	<td>
506	<p>
507	one_div_two_pi
508	</p>
509	</td>
510	<td>
511	<p>
512	1/(2π)
513	</p>
514	</td>
515	<td>
516	<p>
517	1.59155
518	</p>
519	</td>
520	<td>
521	<p>
522	Widely used
523	</p>
524	</td>
525	</tr>
526	<tr>
527	<td>
528	<p>
529	root_pi
530	</p>
531	</td>
532	<td>
533	<p>
534	√π
535	</p>
536	</td>
537	<td>
538	<p>
539	1.77245
540	</p>
541	</td>
542	<td>
543	<p>
544	Widely used
545	</p>
546	</td>
547	</tr>
548	<tr>
549	<td>
550	<p>
551	root_half_pi
552	</p>
553	</td>
554	<td>
555	<p>
556	√ π/2
557	</p>
558	</td>
559	<td>
560	<p>
561	1.25331
562	</p>
563	</td>
564	<td>
565	<p>
566	Widely used
567	</p>
568	</td>
569	</tr>
570	<tr>
571	<td>
572	<p>
573	root_two_pi
574	</p>
575	</td>
576	<td>
577	<p>
578	√ π*2
579	</p>
580	</td>
581	<td>
582	<p>
583	2.50662
584	</p>
585	</td>
586	<td>
587	<p>
588	Widely used
589	</p>
590	</td>
591	</tr>
592	<tr>
593	<td>
594	<p>
595	one_div_root_pi
596	</p>
597	</td>
598	<td>
599	<p>
600	1/√π
601	</p>
602	</td>
603	<td>
604	<p>
605	0.564189
606	</p>
607	</td>
608	<td>
609	</td>
610	</tr>
611	<tr>
612	<td>
613	<p>
614	one_div_root_two_pi
615	</p>
616	</td>
617	<td>
618	<p>
619	1/√(2π)
620	</p>
621	</td>
622	<td>
623	<p>
624	0.398942
625	</p>
626	</td>
627	<td>
628	</td>
629	</tr>
630	<tr>
631	<td>
632	<p>
633	root_one_div_pi
634	</p>
635	</td>
636	<td>
637	<p>
638	√(1/π
639	</p>
640	</td>
641	<td>
642	<p>
643	0.564189
644	</p>
645	</td>
646	<td>
647	</td>
648	</tr>
649	<tr>
650	<td>
651	<p>
652	pi_minus_three
653	</p>
654	</td>
655	<td>
656	<p>
657	π-3
658	</p>
659	</td>
660	<td>
661	<p>
662	0.141593
663	</p>
664	</td>
665	<td>
666	</td>
667	</tr>
668	<tr>
669	<td>
670	<p>
671	four_minus_pi
672	</p>
673	</td>
674	<td>
675	<p>
676	4 -π
677	</p>
678	</td>
679	<td>
680	<p>
681	0.858407
682	</p>
683	</td>
684	<td>
685	</td>
686	</tr>
687	<tr>
688	<td>
689	<p>
690	pi_pow_e
691	</p>
692	</td>
693	<td>
694	<p>
695	π<sup>e</sup>
696	</p>
697	</td>
698	<td>
699	<p>
700	22.4591
701	</p>
702	</td>
703	<td>
704	</td>
705	</tr>
706	<tr>
707	<td>
708	<p>
709	pi_sqr
710	</p>
711	</td>
712	<td>
713	<p>
714	π<sup>2</sup>
715	</p>
716	</td>
717	<td>
718	<p>
719	9.86960
720	</p>
721	</td>
722	<td>
723	</td>
724	</tr>
725	<tr>
726	<td>
727	<p>
728	pi_sqr_div_six
729	</p>
730	</td>
731	<td>
732	<p>
733	π<sup>2</sup>/6
734	</p>
735	</td>
736	<td>
737	<p>
738	1.64493
739	</p>
740	</td>
741	<td>
742	</td>
743	</tr>
744	<tr>
745	<td>
746	<p>
747	pi_cubed
748	</p>
749	</td>
750	<td>
751	<p>
752	π<sup>3</sup>
753	</p>
754	</td>
755	<td>
756	<p>
757	31.00627
758	</p>
759	</td>
760	<td>
761	</td>
762	</tr>
763	<tr>
764	<td>
765	<p>
766	cbrt_pi
767	</p>
768	</td>
769	<td>
770	<p>
771	√<sup>3</sup> π
772	</p>
773	</td>
774	<td>
775	<p>
776	1.46459
777	</p>
778	</td>
779	<td>
780	</td>
781	</tr>
782	<tr>
783	<td>
784	<p>
785	one_div_cbrt_pi
786	</p>
787	</td>
788	<td>
789	<p>
790	1/√<sup>3</sup> π
791	</p>
792	</td>
793	<td>
794	<p>
795	0.682784
796	</p>
797	</td>
798	<td>
799	</td>
800	</tr>
801	<tr>
802	<td>
803	<p>
804	<span class="bold"><strong>Euler's e and related</strong></span>
805	</p>
806	</td>
807	<td>
808	</td>
809	<td>
810	</td>
811	<td>
812	</td>
813	</tr>
814	<tr>
815	<td>
816	<p>
817	e
818	</p>
819	</td>
820	<td>
821	<p>
822	e
823	</p>
824	</td>
825	<td>
826	<p>
827	2.71828
828	</p>
829	</td>
830	<td>
831	<p>
832	<a href="http://en.wikipedia.org/wiki/E_(mathematical_constant)" target="_top">Euler's
833	constant e</a>
834	</p>
835	</td>
836	</tr>
837	<tr>
838	<td>
839	<p>
840	exp_minus_half
841	</p>
842	</td>
843	<td>
844	<p>
845	e <sup>-1/2</sup>
846	</p>
847	</td>
848	<td>
849	<p>
850	0.606530
851	</p>
852	</td>
853	<td>
854	</td>
855	</tr>
856	<tr>
857	<td>
858	<p>
859	e_pow_pi
860	</p>
861	</td>
862	<td>
863	<p>
864	e <sup>π</sup>
865	</p>
866	</td>
867	<td>
868	<p>
869	23.14069
870	</p>
871	</td>
872	<td>
873	</td>
874	</tr>
875	<tr>
876	<td>
877	<p>
878	root_e
879	</p>
880	</td>
881	<td>
882	<p>
883	√ e
884	</p>
885	</td>
886	<td>
887	<p>
888	1.64872
889	</p>
890	</td>
891	<td>
892	</td>
893	</tr>
894	<tr>
895	<td>
896	<p>
897	log10_e
898	</p>
899	</td>
900	<td>
901	<p>
902	log10(e)
903	</p>
904	</td>
905	<td>
906	<p>
907	0.434294
908	</p>
909	</td>
910	<td>
911	</td>
912	</tr>
913	<tr>
914	<td>
915	<p>
916	one_div_log10_e
917	</p>
918	</td>
919	<td>
920	<p>
921	1/log10(e)
922	</p>
923	</td>
924	<td>
925	<p>
926	2.30258
927	</p>
928	</td>
929	<td>
930	</td>
931	</tr>
932	<tr>
933	<td>
934	<p>
935	<span class="bold"><strong>Trigonometric</strong></span>
936	</p>
937	</td>
938	<td>
939	</td>
940	<td>
941	</td>
942	<td>
943	</td>
944	</tr>
945	<tr>
946	<td>
947	<p>
948	degree
949	</p>
950	</td>
951	<td>
952	<p>
953	radians = π / 180
954	</p>
955	</td>
956	<td>
957	<p>
958	0.017453
959	</p>
960	</td>
961	<td>
962	</td>
963	</tr>
964	<tr>
965	<td>
966	<p>
967	radian
968	</p>
969	</td>
970	<td>
971	<p>
972	degrees = 180 / π
973	</p>
974	</td>
975	<td>
976	<p>
977	57.2957
978	</p>
979	</td>
980	<td>
981	</td>
982	</tr>
983	<tr>
984	<td>
985	<p>
986	sin_one
987	</p>
988	</td>
989	<td>
990	<p>
991	sin(1)
992	</p>
993	</td>
994	<td>
995	<p>
996	0.841470
997	</p>
998	</td>
999	<td>
1000	</td>
1001	</tr>
1002	<tr>
1003	<td>
1004	<p>
1005	cos_one
1006	</p>
1007	</td>
1008	<td>
1009	<p>
1010	cos(1)
1011	</p>
1012	</td>
1013	<td>
1014	<p>
1015	0.54030
1016	</p>
1017	</td>
1018	<td>
1019	</td>
1020	</tr>
1021	<tr>
1022	<td>
1023	<p>
1024	sinh_one
1025	</p>
1026	</td>
1027	<td>
1028	<p>
1029	sinh(1)
1030	</p>
1031	</td>
1032	<td>
1033	<p>
1034	1.17520
1035	</p>
1036	</td>
1037	<td>
1038	</td>
1039	</tr>
1040	<tr>
1041	<td>
1042	<p>
1043	cosh_one
1044	</p>
1045	</td>
1046	<td>
1047	<p>
1048	cosh(1)
1049	</p>
1050	</td>
1051	<td>
1052	<p>
1053	1.54308
1054	</p>
1055	</td>
1056	<td>
1057	</td>
1058	</tr>
1059	<tr>
1060	<td>
1061	<p>
1062	<span class="bold"><strong>Phi</strong></span>
1063	</p>
1064	</td>
1065	<td>
1066	<p>
1067	Phidias golden ratio
1068	</p>
1069	</td>
1070	<td>
1071	<p>
1072	<a href="http://en.wikipedia.org/wiki/Golden_ratio" target="_top">Phidias golden
1073	ratio</a>
1074	</p>
1075	</td>
1076	<td>
1077	</td>
1078	</tr>
1079	<tr>
1080	<td>
1081	<p>
1082	phi
1083	</p>
1084	</td>
1085	<td>
1086	<p>
1087	(1 + √5) /2
1088	</p>
1089	</td>
1090	<td>
1091	<p>
1092	1.61803
1093	</p>
1094	</td>
1095	<td>
1096	<p>
1097	finance
1098	</p>
1099	</td>
1100	</tr>
1101	<tr>
1102	<td>
1103	<p>
1104	ln_phi
1105	</p>
1106	</td>
1107	<td>
1108	<p>
1109	ln(φ)
1110	</p>
1111	</td>
1112	<td>
1113	<p>
1114	0.48121
1115	</p>
1116	</td>
1117	<td>
1118	</td>
1119	</tr>
1120	<tr>
1121	<td>
1122	<p>
1123	one_div_ln_phi
1124	</p>
1125	</td>
1126	<td>
1127	<p>
1128	1/ln(φ)
1129	</p>
1130	</td>
1131	<td>
1132	<p>
1133	2.07808
1134	</p>
1135	</td>
1136	<td>
1137	</td>
1138	</tr>
1139	<tr>
1140	<td>
1141	<p>
1142	<span class="bold"><strong>Euler's Gamma</strong></span>
1143	</p>
1144	</td>
1145	<td>
1146	</td>
1147	<td>
1148	</td>
1149	<td>
1150	</td>
1151	</tr>
1152	<tr>
1153	<td>
1154	<p>
1155	euler
1156	</p>
1157	</td>
1158	<td>
1159	<p>
1160	euler
1161	</p>
1162	</td>
1163	<td>
1164	<p>
1165	0.577215
1166	</p>
1167	</td>
1168	<td>
1169	<p>
1170	<a href="http://en.wikipedia.org/wiki/Euler%E2%80%93Mascheroni_constant" target="_top">Euler-Mascheroni
1171	gamma constant</a>
1172	</p>
1173	</td>
1174	</tr>
1175	<tr>
1176	<td>
1177	<p>
1178	one_div_euler
1179	</p>
1180	</td>
1181	<td>
1182	<p>
1183	1/euler
1184	</p>
1185	</td>
1186	<td>
1187	<p>
1188	1.73245
1189	</p>
1190	</td>
1191	<td>
1192	</td>
1193	</tr>
1194	<tr>
1195	<td>
1196	<p>
1197	euler_sqr
1198	</p>
1199	</td>
1200	<td>
1201	<p>
1202	euler<sup>2</sup>
1203	</p>
1204	</td>
1205	<td>
1206	<p>
1207	0.333177
1208	</p>
1209	</td>
1210	<td>
1211	</td>
1212	</tr>
1213	<tr>
1214	<td>
1215	<p>
1216	<span class="bold"><strong>Misc</strong></span>
1217	</p>
1218	</td>
1219	<td>
1220	</td>
1221	<td>
1222	</td>
1223	<td>
1224	</td>
1225	</tr>
1226	<tr>
1227	<td>
1228	<p>
1229	zeta_two
1230	</p>
1231	</td>
1232	<td>
1233	<p>
1234	ζ(2)
1235	</p>
1236	</td>
1237	<td>
1238	<p>
1239	1.64493
1240	</p>
1241	</td>
1242	<td>
1243	<p>
1244	<a href="http://en.wikipedia.org/wiki/Riemann_zeta_function" target="_top">Riemann
1245	zeta function</a>
1246	</p>
1247	</td>
1248	</tr>
1249	<tr>
1250	<td>
1251	<p>
1252	zeta_three
1253	</p>
1254	</td>
1255	<td>
1256	<p>
1257	ζ(3)
1258	</p>
1259	</td>
1260	<td>
1261	<p>
1262	1.20205
1263	</p>
1264	</td>
1265	<td>
1266	<p>
1267	<a href="http://en.wikipedia.org/wiki/Riemann_zeta_function" target="_top">Riemann
1268	zeta function</a>
1269	</p>
1270	</td>
1271	</tr>
1272	<tr>
1273	<td>
1274	<p>
1275	catalan
1276	</p>
1277	</td>
1278	<td>
1279	<p>
1280	<span class="emphasis"><em>K</em></span>
1281	</p>
1282	</td>
1283	<td>
1284	<p>
1285	0.915965
1286	</p>
1287	</td>
1288	<td>
1289	<p>
1290	<a href="http://mathworld.wolfram.com/CatalansConstant.html" target="_top">Catalan
1291	(or Glaisher) combinatorial constant</a>
1292	</p>
1293	</td>
1294	</tr>
1295	<tr>
1296	<td>
1297	<p>
1298	glaisher
1299	</p>
1300	</td>
1301	<td>
1302	<p>
1303	<span class="emphasis"><em>A</em></span>
1304	</p>
1305	</td>
1306	<td>
1307	<p>
1308	1.28242
1309	</p>
1310	</td>
1311	<td>
1312	<p>
1313	<a href="https://oeis.org/A074962/constant" target="_top">Decimal expansion
1314	of Glaisher-Kinkelin constant</a>
1315	</p>
1316	</td>
1317	</tr>
1318	<tr>
1319	<td>
1320	<p>
1321	khinchin
1322	</p>
1323	</td>
1324	<td>
1325	<p>
1326	<span class="emphasis"><em>k</em></span>
1327	</p>
1328	</td>
1329	<td>
1330	<p>
1331	2.685452
1332	</p>
1333	</td>
1334	<td>
1335	<p>
1336	<a href="https://oeis.org/A002210/constant" target="_top">Decimal expansion
1337	of Khinchin constant</a>
1338	</p>
1339	</td>
1340	</tr>
1341	<tr>
1342	<td>
1343	<p>
1344	extreme_value_skewness
1345	</p>
1346	</td>
1347	<td>
1348	<p>
1349	12√6 ζ(3)/ π<sup>3</sup>
1350	</p>
1351	</td>
1352	<td>
1353	<p>
1354	1.139547
1355	</p>
1356	</td>
1357	<td>
1358	<p>
1359	Extreme value distribution
1360	</p>
1361	</td>
1362	</tr>
1363	<tr>
1364	<td>
1365	<p>
1366	rayleigh_skewness
1367	</p>
1368	</td>
1369	<td>
1370	<p>
1371	2√π(π-3)/(4 - π)<sup>3/2</sup>
1372	</p>
1373	</td>
1374	<td>
1375	<p>
1376	0.631110
1377	</p>
1378	</td>
1379	<td>
1380	<p>
1381	Rayleigh distribution skewness
1382	</p>
1383	</td>
1384	</tr>
1385	<tr>
1386	<td>
1387	<p>
1388	rayleigh_kurtosis_excess
1389	</p>
1390	</td>
1391	<td>
1392	<p>
1393	-(6π<sup>2</sup>-24π+16)/(4-π)<sup>2</sup>
1394	</p>
1395	</td>
1396	<td>
1397	<p>
1398	0.245089
1399	</p>
1400	</td>
1401	<td>
1402	<p>
1403	<a href="http://en.wikipedia.org/wiki/Rayleigh_distribution" target="_top">Rayleigh
1404	distribution kurtosis excess</a>
1405	</p>
1406	</td>
1407	</tr>
1408	<tr>
1409	<td>
1410	<p>
1411	rayleigh_kurtosis
1412	</p>
1413	</td>
1414	<td>
1415	<p>
1416	3+(6π<sup>2</sup>-24π+16)/(4-π)<sup>2</sup>
1417	</p>
1418	</td>
1419	<td>
1420	<p>
1421	3.245089
1422	</p>
1423	</td>
1424	<td>
1425	<p>
1426	Rayleigh distribution kurtosis
1427	</p>
1428	</td>
1429	</tr>
1430	</tbody>
1431	</table></div>
1432	</div>
1433	<br class="table-break"><div class="note"><table border="0" summary="Note">
1434	<tr>
1435	<td rowspan="2" align="center" valign="top" width="25"><img alt="[Note]" src="../../../../../doc/src/images/note.png"></td>
1436	<th align="left">Note</th>
1437	</tr>
1438	<tr><td align="left" valign="top"><p>
1439	Integer values are <span class="bold"><strong>not included</strong></span> in this
1440	list of math constants, however interesting, because they can be so easily
1441	and exactly constructed, even for UDT, for example: <code class="computeroutput"><span class="keyword">static_cast</span><span class="special"><</span><span class="identifier">cpp_float</span><span class="special">>(</span><span class="number">42</span><span class="special">)</span></code>.
1442	</p></td></tr>
1443	</table></div>
1444	<div class="tip"><table border="0" summary="Tip">
1445	<tr>
1446	<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
1447	<th align="left">Tip</th>
1448	</tr>
1449	<tr><td align="left" valign="top"><p>
1450	If you know the approximate value of the constant, you can search for the
1451	value to find Boost.Math chosen name in this table.
1452	</p></td></tr>
1453	</table></div>
1454	<div class="tip"><table border="0" summary="Tip">
1455	<tr>
1456	<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
1457	<th align="left">Tip</th>
1458	</tr>
1459	<tr><td align="left" valign="top"><p>
1460	Bernoulli numbers are available at <a class="link" href="number_series/bernoulli_numbers.html" title="Bernoulli Numbers">Bernoulli
1461	numbers</a>.
1462	</p></td></tr>
1463	</table></div>
1464	<div class="tip"><table border="0" summary="Tip">
1465	<tr>
1466	<td rowspan="2" align="center" valign="top" width="25"><img alt="[Tip]" src="../../../../../doc/src/images/tip.png"></td>
1467	<th align="left">Tip</th>
1468	</tr>
1469	<tr><td align="left" valign="top"><p>
1470	Factorials are available at <a class="link" href="factorials/sf_factorial.html" title="Factorial">factorial</a>.
1471	</p></td></tr>
1472	</table></div>
1473	</div>
1474	<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
1475	<td align="left"></td>
1476	<td align="right"><div class="copyright-footer">Copyright © 2006-2010, 2012-2014 Nikhar Agrawal,
1477	Anton Bikineev, Paul A. Bristow, Marco Guazzone, Christopher Kormanyos, Hubert
1478	Holin, Bruno Lalande, John Maddock, Jeremy Murphy, Johan Råde, Gautam Sewani,
1479	Benjamin Sobotta, Thijs van den Berg, Daryle Walker and Xiaogang Zhang<p>
1480	Distributed under the Boost Software License, Version 1.0. (See accompanying
1481	file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
1482	</p>
1483	</div></td>
1484	</tr></table>
1485	<hr>
1486	<div class="spirit-nav">
1487	<a accesskey="p" href="tutorial/user_def.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../constants.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="new_const.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a>
1488	</div>
1489	</body>
1490	</html>