17525619domain: NAppears in sequencesNumber of matchings in graph P_{4} X P_{n}.at n=7A033507Number of matchings in graph P_{7} X P_{n}.at n=4A033510Triangle read by rows: T(n,k) (1 <= k <= n) = number of monomer-dimer tilings of an n X k board.at n=24A210662