def different_layers(x, nmon):
    """
    Test if monomers a pair of monomers are in separate layers (based on initial configuration build procedure)
    :param x : length 2 list of monomer numbers (calculated using hbonds.System.number_residues)
    :param nmon: number of monomers per layer (int)
    :return: True / False (bool)
    """

    different = False
    layer = [a // nmon for a in x]
    if layer[0] != layer[1]:
        different = True

    return different