OFFSET
0,5
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Sech[ArcTanh[x]Log[x+1]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Apr 23 2023 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Definition clarified by Harvey P. Dale, Apr 23 2023
STATUS
approved