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A013166
Expansion of e.g.f.: sech(arctanh(x)+log(x+1))=1-4/2!*x^2+6/3!*x^3+45/4!*x^4-300/5!*x^5...
0
1, 0, -4, 6, 45, -300, -630, 18270, -44415, -1428840, 13608000, 106964550, -3044747475, 2748645900, 674525001150, -6848689097250, -138141621993375, 3761985048822000, 12387014410270500, -1765001060909336250
OFFSET
0,3
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Sech[ArcTanh[x]+Log[x+1]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jan 10 2019 *)
CROSSREFS
Sequence in context: A370619 A077100 A012935 * A174653 A274215 A119944
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Definition clarified by Harvey P. Dale, Jan 10 2019
STATUS
approved