A012460 cos(arctan(x)^2)=1-12/4!*x^4+480/6!*x^6-27888/8!*x^8...

1, 0, -12, 480, -27888, 2353920, -274245312, 41974872576, -8068087373568, 1860842339721216, -486190504963034112, 129225947748233994240, -22917287813817561968640, -13673939410058068058112000

Offset

0,3

Links

Table of n, a(n) for n=0..13.

Mathematica

With[{nn=30}, Take[CoefficientList[Series[Cos[ArcTan[x]^2], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Oct 07 2016 *)

Crossrefs

Sequence in context: A009083 A012681 A009168 * A012685 A012465 A012394

Adjacent sequences: A012457 A012458 A012459 * A012461 A012462 A012463

Keyword

sign

Author

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

Extensions

Definition clarified by Harvey P. Dale, Oct 07 2016

Status

approved