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A012048
arctanh(sin(tanh(x)))=x-1/3!*x^3+1/5!*x^5+55/7!*x^7-2207/9!*x^9...
0
1, -1, 1, 55, -2207, 79727, -2834207, 81045991, 1107720001, -715785186337, 165075476417857, -44818254949260905, 14626040239803925921, -5177396773524357363889, 1885895392048206524730145
OFFSET
0,4
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[ArcTanh[Sin[Tanh[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Mar 07 2017 *)
CROSSREFS
Sequence in context: A346325 A240687 A053113 * A215860 A020536 A212788
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved