{{alias}}( p )
    Returns the excess kurtosis of a geometric distribution with success
    probability `p`.

    If `p < 0` or `p > 1`, the function returns `NaN`.

    Parameters
    ----------
    p: number
        Success probability.

    Returns
    -------
    out: number
        Excess kurtosis.

    Examples
    --------
    > var v = {{alias}}( 0.1 )
    ~6.011
    > v = {{alias}}( 0.5 )
    6.5

    See Also
    --------