13535280domain: NAppears in sequencesNumber of (undirected) Hamiltonian paths in the n X n grid graph.at n=6A120443Number of Hamiltonian paths in P_7 X P_n.at n=6A358794Triangle read by rows: T(n,k) is the number of paths traveling orthogonally on an n X k grid that visit every cell.at n=27A366399