Number of 5Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row.
A221627
Number of 5Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row.
Terms
- a(0) =1a(1) =6a(2) =1818a(3) =1130256a(4) =3451956516
External references
- oeis: A221627