Number A(n,k) of permutations p of [n] having no index i with |p(i)-i| = k; square array A(n,k), n>=0, k>=0, read by antidiagonals.

A306512

Number A(n,k) of permutations p of [n] having no index i with |p(i)-i| = k; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Terms

    a(0) =1a(1) =1a(2) =0a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =1a(9) =2a(10) =1a(11) =1a(12) =2a(13) =2a(14) =9a(15) =1a(16) =1a(17) =2a(18) =3a(19) =5a(20) =44a(21) =1a(22) =1a(23) =2a(24) =6a(25) =9a(26) =21a(27) =265a(28) =1a(29) =1

External references