8459468955domain: NAppears in sequencesTriangle read by rows: T(n,k) = number of tilings of a n X k rectangle using 2 X 2 and 1 X 1 tiles and dominoes, n >= 0, k = 0..n.at n=27A352589Number of tilings of an n X n square using dominoes, monominoes and 2 X 2 tiles.at n=6A353777