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A321115 Number of permutations p of [n] such that in 0p the largest up-jump equals eight and no down-jump is larger than 2.

%I A321115 #5 Oct 27 2018 16:23:04
%S A321115 218,1672,11840,80724,540122,3577200,23538730,154134422,1004867492,
%T A321115 6532643538,42400841816,274916251180,1781266093356,11536471789526,
%U A321115 74699007947826,483632170943926,3131266103627660,20275073235017968,131300482646184366,850449366760216588
%N A321115 Number of permutations p of [n] such that in 0p the largest up-jump equals eight and no down-jump is larger than 2.
%H A321115 Alois P. Heinz, <a href="/A321115/b321115.txt">Table of n, a(n) for n = 8..1000</a>
%p A321115 b:= proc(u, o, k) option remember; `if`(u+o=0, 1,
%p A321115       add(b(u-j, o+j-1, k), j=1..min(2, u))+
%p A321115       add(b(u+j-1, o-j, k), j=1..min(k, o)))
%p A321115     end:
%p A321115 a:= n-> (k-> b(0, n, k)-b(0, n, k-1))(8):
%p A321115 seq(a(n), n=8..30);
%Y A321115 Column k=8 of A291680.
%K A321115 nonn
%O A321115 8,1
%A A321115 _Alois P. Heinz_, Oct 27 2018