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A009209
Expansion of e.g.f.: exp(sin(x))/exp(x).
2
1, 0, 0, -1, 0, 1, 10, -1, -56, -279, 246, 4619, 14388, -53195, -556478, -864865, 13276912, 90192753, -72903378, -3987888493, -16957067028, 101506932205, 1411655530330, 2206092853799, -70455418153496, -549095655588183, 1428569363164230
OFFSET
0,7
FORMULA
a(0) = 1; a(n) = Sum_{k=1..floor((n-1)/2)} (-1)^k * binomial(n-1,2*k) * a(n-2*k-1). - Ilya Gutkovskiy, Apr 09 2022
MATHEMATICA
With[{nn=30}, CoefficientList[Series[Exp[Sin[x]]/Exp[x], {x, 0, nn}], x]Range[0, nn]!] (* Harvey P. Dale, Jun 27 2012 *)
PROG
(PARI) my(x='x+O('x^30)); Vec(serlaplace(exp(sin(x))/exp(x))) \\ Michel Marcus, Apr 09 2022
CROSSREFS
Sequence in context: A050304 A143471 A286921 * A009227 A305996 A030526
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
Definition clarified by Harvey P. Dale, Jun 27 2012
STATUS
approved