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A013297
-arctan(log(x+1)-arctanh(x))=1/2!*x^2+6/4!*x^4+90/6!*x^6+2520/8!*x^8...
0
0, 1, 6, 90, 2520, 120960, 9979200, 1377295920, 285145660800, 78922558915200, 27250976424672000, 11359413770434329600, 5628391828843104921600, 3284252230408078849920000, 2238997166752030045320960000
OFFSET
0,3
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[-ArcTan[Log[x+1]-ArcTanh[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Ray Chandler, Nov 29 2016 *)
CROSSREFS
Sequence in context: A177289 A177290 A000680 * A232979 A218758 A219304
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved