672160domain: NAppears in sequencesG.f. satisfies: A(x) = (1 + x + x^2) * A(x^2)^4.at n=23A237648Number of nonequivalent ways to place n non-attacking rooks on an n X n board with no rook on 2 main diagonals up to rotations and reflections of the board.at n=11A292080