cp's OEIS Frontend

A264496 Number of permutations of [n] with exactly nine (possibly overlapping) occurrences of the generalized pattern 13-2.

%I A264496 #7 Nov 14 2015 18:43:05
%S A264496 1,256,11115,258564,4235959,55145400,609428105,5954337792,52838734860,
%T A264496 433992926048,3345094317796,24447556164496,170782982829160,
%U A264496 1147577406468288,7455096381483206,47017233051466444,288854847620573814,1733658007070671968,10189610103251200265
%N A264496 Number of permutations of [n] with exactly nine (possibly overlapping) occurrences of the generalized pattern 13-2.
%H A264496 Alois P. Heinz, <a href="/A264496/b264496.txt">Table of n, a(n) for n = 7..500</a>
%p A264496 b:= proc(u, o) option remember; `if`(u+o=0, 1, add(
%p A264496        b(u-j, o+j-1), j=1..u) +add(convert(series(
%p A264496        b(u+j-1, o-j)*x^(j-1), x, 10),polynom), j=1..o))
%p A264496     end:
%p A264496 a:= n-> coeff(b(n, 0), x, 9):
%p A264496 seq(a(n), n=7..25);
%Y A264496 Column k=9 of A263776.
%K A264496 nonn
%O A264496 7,2
%A A264496 _Alois P. Heinz_, Nov 14 2015