102645domain: NAppears in sequencesA recursive triangle sequence: A(n,k)=k^2*(A(n - 1, k - 1) + A(n - 1, k)).at n=23A156137Number of lower triangles of a 4 X 4 0..n array with no element differing from any of its horizontal or vertical neighbors by more than one.at n=15A194933