Number of n X n arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order.

A222000

Number of n X n arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order.

Terms

    a(0) =1a(1) =2a(2) =22a(3) =2470a(4) =16011558

External references