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A024282 Expansion of e.g.f. tanh(x)*sin(sin(x))/2, even powers only. 2
0, 1, -8, 124, -3168, 121232, -6609664, 491033408, -47878820864, 5942382135552, -915386669357056, 171409533142952960, -38347910567533715456, 10102227232688591245312, -3095277524018668920373248 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..100

FORMULA

a(n) ~ (-1)^(n+1) * sinh(sinh(Pi/2)) * 2^(2*n+1) * (2*n)! / Pi^(2*n+1). - Vaclav Kotesovec, Apr 20 2014

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Tanh[x]Sin[Sin[x]]/2, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Oct 20 2013 *)

PROG

(PARI) A024282=n->{my(t=x+O(x^(2*n+!n))); polcoeff(tanh(t)*sin(sin(t)), n*2, x)/2*(2*n)!} \\ M. F. Hasler, Feb 09 2014

CROSSREFS

Cf. A009833.

Sequence in context: A302356 A069459 A254125 * A231638 A065082 A053058

Adjacent sequences:  A024279 A024280 A024281 * A024283 A024284 A024285

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

Prior Mathematica program replaced by Harvey P. Dale, Oct 20 2013

Clarified definition, Joerg Arndt, Feb 09 2014

STATUS

approved

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Last modified October 21 06:03 EDT 2018. Contains 316405 sequences. (Running on oeis4.)