def phi31_v_from_i_skow(phi31_i):
    """
    Calculates the V band phi31 for the given I band phi3 using the
    relationship found in Skowron et al. (2016).

    (Skowron et al., 2016) (6)

    Parameters
    ----------
    phi31_i : float64
        The I band phi31 of the star.

    Returns
    -------
    phi31_v : float64
        The calculated V band phi31 of the star.
    """
    return 0.122 * phi31_i ** 2 - 0.750 * phi31_i + 5.331