def rdiv(denom, result):
    """
    Calculates the inverse of a div operation.

    The *denom* parameter specifies the denominator of the original div (//)
    operation. In this implementation, *denom* must be greater than 0. The
    *result* parameter specifies the result of the div operation.

    The function returns the set of potential numerators.
    """
    if denom <= 0:
        raise ValueError('invalid denominator')
    return range(result * denom, result * denom + denom)