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%I #7 Feb 09 2015 10:34:15
%S 130,18196,1027497,35855578,920132845,19024724767,334824869566,
%T 5199938158961,73073359931844,946309985456857,11449696018832655,
%U 130815643776548834,1423250326223813866,14845562100052915605,149281547622659687547,1453772869428542126084
%N Number of isoscent sequences of length n with exactly seven descents.
%H Joerg Arndt and Alois P. Heinz, <a href="/A243480/b243480.txt">Table of n, a(n) for n = 13..100</a>
%t b[n_, i_, t_] := b[n, i, t] = If[n < 1, 1, Expand[Sum[ If[j < i, x, 1] *b[n - 1, j, t + If[j == i, 1, 0]], {j, 0, t + 1}]]]; a[n_] := Coefficient[b[n - 1, 0, 0], x, 7]; Table[a[n], {n, 13, 40}] (* _Jean-François Alcover_, Feb 09 2015, after A242352 *)
%Y Column k=7 of A242352.
%K nonn
%O 13,1
%A _Joerg Arndt_ and _Alois P. Heinz_, Jun 05 2014