PYRAMID_NUM</b> returns the N-th pyramidal number.
        </li>
        <li>
          <b>R8_ACOSH</b> returns the inverse hyperbolic cosine of a number.
        </li>
        <li>
          <b>R8_ASINH</b> returns the inverse hyperbolic sine of a number.
        </li>
        <li>
          <b>R8_ATANH</b> returns the inverse hyperbolic tangent of a number.
        </li>
        <li>
          <b>R8_CAS</b> returns the "casine" of an R8 value.
        </li>
        <li>
          <b>R8_CHOOSE</b> computes