A228672 Number of permutations of [n] having a shortest ascending run of length 5.

1, 0, 0, 0, 0, 251, 922, 1582, 2572, 4002, 756755, 6029297, 31742676, 120956707, 398182782, 12794989968, 166170816448, 1418774022895, 9698826682676, 55499002033421, 894582818429967, 14637215156295242, 177486208140377619, 1730337098015002802

Offset: 5

Author

Alois P. Heinz, Aug 29 2013

Keywords

• nonn

Links

• Alois P. Heinz and Vaclav Kotesovec, Table of n, a(n) for n = 5..350 (first 100 terms from Alois P. Heinz)

Crossrefs

Column k=5 of A064315.

Formula

a(n) ~ c * d^n * n!, where d = 0.4206507959..., c = 0.1811532007... . - Vaclav Kotesovec, Sep 07 2014