A009743 Expansion of e.g.f. tan(x)*sin(tanh(x)), even powers only.

0, 2, -4, 198, -4040, 316874, -19176268, 2374489614, -282825044624, 52279148694674, -10130169154611604, 2647521503418566742, -750173159912329738328, 264926794785670147533914, -102608322417098838227114716, 47204299500814419684790058910

Offset

0,2

Links

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

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Tan[x]*Sin[Tanh[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, May 28 2016 *)

Prog

(PARI) x='x+O('x^50); v=Vec(serlaplace(tan(x)*sin(tanh(x)))); concat([0], vector(#v\2, n, v[2*n-1])) \\ G. C. Greubel, Mar 04 2018

Crossrefs

Sequence in context: A307556 A018637 A018647 * A009796 A018651 A068479

Adjacent sequences: A009740 A009741 A009742 * A009744 A009745 A009746

Keyword

sign

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

More terms from and prior Mathematica program removed by Harvey P. Dale, May 28 2016

Status

approved