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A012424
cos(arctan(x)*sin(x))=1-12/4!*x^4+360/6!*x^6-14000/8!*x^8...
0
1, 0, -12, 360, -14000, 826560, -74707776, 9918004096, -1826276458240, 443565659817984, -136830226103770112, 52123659256392435712, -23992831220659002945536, 13113491065080505366691840
OFFSET
0,3
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Cos[ArcTan[x]Sin[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, May 24 2015 *)
CROSSREFS
Sequence in context: A012633 A009079 A012379 * A009165 A012627 A012384
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved