OFFSET
0,4
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Sec[ArcTan[x]-ArcTanh[x]], {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Ray Chandler, Nov 29 2016 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved