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A243478 Number of isoscent sequences of length n with exactly five descents. 2
22, 1546, 46947, 944701, 14745521, 193273378, 2228848403, 23305050081, 225560761204, 2051114040040, 17719591217257, 146674616051322, 1171101886353096, 9067551569835697, 68378670584901547, 504001041740002317, 3641720452674969516, 25859746275607624792 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,1

LINKS

Joerg Arndt and Alois P. Heinz, Table of n, a(n) for n = 10..100

MATHEMATICA

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, 5]; Table[a[n], {n, 10, 40}] (* Jean-Fran├žois Alcover, Feb 09 2015, after A242352 *)

CROSSREFS

Column k=5 of A242352.

Sequence in context: A160309 A033526 A078399 * A245658 A277664 A199836

Adjacent sequences:  A243475 A243476 A243477 * A243479 A243480 A243481

KEYWORD

nonn

AUTHOR

Joerg Arndt and Alois P. Heinz, Jun 05 2014

STATUS

approved

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Last modified July 17 18:47 EDT 2019. Contains 325109 sequences. (Running on oeis4.)