    continued fraction representation (refer to the first continued fraction
          in the implementation discussion below). Note that this continued fraction
          is <span class="emphasis"><em>not</em></span> used in the implementation, and therefore we
          have test data that is fully independent of the code.
        </p>
<h5>
<a name="math_toolkit.special.sf_beta.ibeta_function.h4"></a>
          <span class="phrase"><a name="math_toolkit.special.sf_beta.ibeta_function.implementation"></a><