

A009548


Expansion of e.g.f. sin(x)*sin(tan(x)) (even powers only).


2



0, 2, 0, 32, 1984, 118016, 8529920, 754714880, 79868821504, 9749056634880, 1296267479826432, 165153529347768320, 9993013885707223040, 7114872804447958401024, 5975166564856692622753792
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OFFSET

0,2


LINKS

G. C. Greubel, Table of n, a(n) for n = 0..240


MATHEMATICA

With[{nmax = 50}, CoefficientList[Series[Sin[x]*Sin[Tan[x]], {x, 0, nmax}], x]*Range[0, nmax]!][[1 ;; ;; 2]] (* G. C. Greubel, Jan 20 2018 *)


PROG

(PARI) x='x+O('x^50); v=Vec(serlaplace(sin(x)*sin(tan(x)))); concat([0], vector(#v\2, n, v[2*n1])) // G. C. Greubel, Jan 20 2018


CROSSREFS

Sequence in context: A156504 A009665 A053552 * A172388 A193052 A337817
Adjacent sequences: A009545 A009546 A009547 * A009549 A009550 A009551


KEYWORD

sign


AUTHOR

R. H. Hardin


EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997


STATUS

approved



