A321112 Number of permutations p of [n] such that in 0p the largest up-jump equals five and no down-jump is larger than 2.

10, 58, 340, 2014, 11888, 69274, 401648, 2329526, 13514794, 78445016, 455726404, 2650463368, 15433424116, 89977250572, 525210971550, 3069436719818, 17959557595206, 105203403819650, 616942677047888, 3621795968081798, 21283870741193560, 125201162038738596

Offset: 5

Author

Alois P. Heinz, Oct 27 2018

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 5..1000

Crossrefs

Column k=5 of A291680.

Programs

Maple

b:= proc(u, o, k) option remember; `if`(u+o=0, 1,
      add(b(u-j, o+j-1, k), j=1..min(2, u))+
      add(b(u+j-1, o-j, k), j=1..min(k, o)))
    end:
a:= n-> (k-> b(0, n, k)-b(0, n, k-1))(5):
seq(a(n), n=5..30);