681728204domain: NAppears in sequencesNumber of Hamiltonian circuits on 2n X 8 rectangle.at n=4A005391Number of Hamiltonian cycles in P_8 X P_n.at n=9A145418Number of Hamiltonian cycles in P_10 X P_n.at n=7A180504Triangle read by rows: T(m,n) = number of Hamiltonian cycles on m X n grid of points (m >= 2, 2 <= n <= m).at n=42A321172