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A012998 sin(arctan(x)+tan(x))=2*x-8/3!*x^3+72/5!*x^5-3936/7!*x^7... 0
2, -8, 72, -3936, 193920, -21876736, 2967878656, -589063146496, 149737853943808, -48291040167362560, 19310260456438693888, -9310185546185219768320, 5359263862743046978797568 (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[Sin[ArcTan[x]+Tan[x]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Dec 17 2017 *)

CROSSREFS

Sequence in context: A295044 A305000 A013002 * A143760 A064605 A295373

Adjacent sequences:  A012995 A012996 A012997 * A012999 A013000 A013001

KEYWORD

sign

AUTHOR

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

STATUS

approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)