ns the sum of two Laguerre series `c1` + `c2`.  The arguments
    are sequences of coefficients ordered from lowest order term to
    highest, i.e., [1,2,3] represents the series ``P_0 + 2*P_1 + 3*P_2``.

    Parameters
    ----------
    c1, c2 : array_like
        1-D arrays of Laguerre series coefficients ordered from low to
        high.

    Returns
    -------
    out : ndarray
        Array representing the Laguerre series of their sum.

    See Also
    --------
    lagsub, lagmulx, lagmul, lagdiv, lagpow

    Notes
    -----
    Unlike multiplication, division, etc., the sum of two Laguerre series
    is a Laguerre series (without having to "reproject" the result onto
    the basis set) so addition, just like that of "standard" polynomials,
    is simply "component-wise."

    Examples
    --------
    >>> from numpy.polynomial.laguerre import lagadd
    >>> lagadd([1, 2, 3], [1, 2, 3, 4])
    array([2.,  4.,  6.,  4.])


    )