A009606 Expansion of e.g.f. sinh(tan(x))*sin(x) (even powers only).

0, 2, 8, 168, 5760, 310304, 23894144, 2481859968, 333725331456, 56329065984512, 11650274400684032, 2895770490247219200, 851263005980215443456, 292012329049579197046784, 115560631410392130840461312, 52240866338892496235877335040

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..239

Formula

a(n) = 2*A024259(n).

Maple

seq(factorial(k) * coeftayl(sinh(tan(x))*sin(x), x = 0, k), k=0..30, 2); # Muniru A Asiru, Feb 01 2018

Mathematica

With[{nn=40}, Take[CoefficientList[Series[Sinh[Tan[x]]Sin[x], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Dec 27 2011 *)

Prog

(PARI) x='x+O('x^40); v=Vec(serlaplace(sinh(tan(x))*sin(x))); concat([0], vector(#v\2, n, v[2*n-1])) \\ G. C. Greubel, Jan 30 2018 *)

Crossrefs

Cf. A024259.

Sequence in context: A012540 A346164 A175538 * A009682 A076548 A167009

Adjacent sequences: A009603 A009604 A009605 * A009607 A009608 A009609

Keyword

nonn

Author

R. H. Hardin

Extensions

Extended and signs tested by Olivier Gérard, Mar 15 1997

More terms from Harvey P. Dale, Dec 27 2011

Status

approved