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A243233 Number of isoscent sequences of length n with exactly seven ascents.

%I A243233 #4 Jun 01 2014 18:44:51
%S A243233 436,45146,1830826,45369299,826196076,12168531813,153430719591,
%T A243233 1718168937922,17525279293159,165802561604726,1474718822704304,
%U A243233 12459599973722036,100805357136035992,786035745070774366,5938016635175121413,43645066989439738813,313228673357655892678
%N A243233 Number of isoscent sequences of length n with exactly seven ascents.
%H A243233 Joerg Arndt and Alois P. Heinz, <a href="/A243233/b243233.txt">Table of n, a(n) for n = 12..100</a>
%p A243233 b:= proc(n, i, t) option remember; `if`(n<1, 1, expand(add(
%p A243233       `if`(j>i, x, 1) *b(n-1, j, t+`if`(j=i, 1, 0)), j=0..t+1)))
%p A243233     end:
%p A243233 a:= n-> coeff(b(n-1, 0$2), x, 7):
%p A243233 seq(a(n), n=12..35);
%Y A243233 Column k=7 of A242351.
%K A243233 nonn
%O A243233 12,1
%A A243233 _Joerg Arndt_ and _Alois P. Heinz_, Jun 01 2014