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%I #7 Feb 09 2015 10:34:09
%S 2,570,34643,1139465,26298831,479669603,7386945631,100099764774,
%T 1227140160022,13879804132399,146957303797639,1472647088474040,
%U 14087369324642004,129522280702233381,1150891407181302417,9927963973481921295,83454334937159452579
%N Number of isoscent sequences of length n with exactly six descents.
%H Joerg Arndt and Alois P. Heinz, <a href="/A243479/b243479.txt">Table of n, a(n) for n = 11..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, 6]; Table[a[n], {n, 11, 40}] (* _Jean-François Alcover_, Feb 09 2015, after A242352 *)
%Y Column k=6 of A242352.
%K nonn
%O 11,1
%A _Joerg Arndt_ and _Alois P. Heinz_, Jun 05 2014
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