ction.
        </li>
        <li>
          <b>R8_FACTORIAL2</b> computes the double factorial function.
        </li>
        <li>
          <b>R8_GAMMA</b> evaluates Gamma(X) for a real argument.
        </li>
        <li>
          <b>R8_GAMMA_LOG</b> evaluates log ( Gamma ( X ) ) for a real argument.
        </li>
        <li>
          <b>R8_HUGE</b> returns a "huge" R8.
        </li>
        <li>
          <b>R8_HYPER_2F1</b> evaluates the hypergeometric function F(A,B,C,X).
        </li>
        <li>