Number of 3Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row.
A221625
Number of 3Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row.
Terms
- a(0) =1a(1) =4a(2) =112a(3) =6120a(4) =738150a(5) =148700748a(6) =49096652080
External references
- oeis: A221625