A012557 - OEIS

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A012557

tan(sinh(x)*arctan(x))=2/2!*x^2-4/4!*x^4+350/6!*x^6-11240/8!*x^8...

2, -4, 350, -11240, 1461658, -167279660, 35689423926, -8594866078032, 2902777731046578, -1163594305273709524, 584328120817240344206, -346295976826690961613880, 244030359200524004600252746

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

Table of n, a(n) for n=0..12.

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Tan[Sinh[x]ArcTan[x]], {x, 0, nn}], x] Range[0, nn]!, {3, -1, 2}]] (* Harvey P. Dale, Mar 01 2015 *)

CROSSREFS

Sequence in context: A012372 A012613 A012618 * A012562 A263959 A216024

Adjacent sequences: A012554 A012555 A012556 * A012558 A012559 A012560

KEYWORD

sign

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

STATUS

approved