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A012137
arctan(arcsin(arctanh(x))) = x + (1/3!)*x^3 + (17/5!)*x^5 + (673/7!)*x^7 + (54305/9!)*x^9 + ...
0
1, 1, 17, 673, 54305, 7334273, 1497501873, 430436005665, 165573876222529, 82074493484054017, 50922938856050558289, 38644611846710150572193, 35205379514991276523808353, 37909794281251146499011279233
OFFSET
0,3
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[ArcTan[ArcSin[ArcTanh[x]]], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jan 18 2020 *)
CROSSREFS
Sequence in context: A009158 A012050 A012157 * A171198 A309410 A201311
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved