463104domain: NAppears in sequencesTriangle read by rows T(n,k): number of undirected cycles of length k in the complete tripartite graph K_{n,n,n} (n = 1...; k = 3..3n).at n=21A296546Number of (undirected) Hamiltonian cycles in the complete tripartite graph K_{n,n,n}.at n=3A307924