753536domain: NAppears in sequencesNumber of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 2.at n=6A123762Number of nonoverlapping placements of one 1 X 1 square and one 2 X 2 square on an n X n board.at n=29A173963E.g.f. satisfies: A'(x) = A(x)^4 * A(-x)^2 with A(0) = 1.at n=8A235321