 the PHI function.
        </li>
        <li>
          <b>POLY_BERNOULLI</b> evaluates the poly-Bernolli numbers with negative index.
        </li>
        <li>
          <b>POLY_COEF_COUNT:</b> polynomial coefficient count given dimension and degree.
        </li>
        <li>
          <b>PRIME</b> returns any of the first PRIME_MAX prime numbers.
        </li>
        <li>
          <b>PSI_VALUES</b> returns some values of the Psi or Digamma function for testing.
        </li>
        <li>
          <b>