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A321113 Number of permutations p of [n] such that in 0p the largest up-jump equals six and no down-jump is larger than 2.

%I A321113 #5 Oct 27 2018 16:19:29
%S A321113 26,170,1078,6772,42366,263548,1626122,9993996,61372356,376754190,
%T A321113 2312742484,14199997152,87223775288,536072840284,3296748123732,
%U A321113 20287763348424,124932460269594,769857062164974,4747179317544360,29291823451184116,180856995405347960
%N A321113 Number of permutations p of [n] such that in 0p the largest up-jump equals six and no down-jump is larger than 2.
%H A321113 Alois P. Heinz, <a href="/A321113/b321113.txt">Table of n, a(n) for n = 6..1000</a>
%p A321113 b:= proc(u, o, k) option remember; `if`(u+o=0, 1,
%p A321113       add(b(u-j, o+j-1, k), j=1..min(2, u))+
%p A321113       add(b(u+j-1, o-j, k), j=1..min(k, o)))
%p A321113     end:
%p A321113 a:= n-> (k-> b(0, n, k)-b(0, n, k-1))(6):
%p A321113 seq(a(n), n=6..30);
%Y A321113 Column k=6 of A291680.
%K A321113 nonn
%O A321113 6,1
%A A321113 _Alois P. Heinz_, Oct 27 2018