li>
          <b>TRIANGLE_NUM</b> returns the N-th triangular number.
        </li>
        <li>
          <b>TRIANGLE_TO_I4</b> converts a triangular coordinate to an integer.
        </li>
        <li>
          <b>VIBONACCI</b> computes the first N Vibonacci numbers.
        </li>
        <li>
          <b>ZECKENDORF</b> produces the Zeckendorf decomposition of a positive integer.
        </li>
        <li>
          <b>ZERNIKE_POLY</b> evaluates a Zernike polynomial at RHO.
        </li>
        <li>
  