A012708 - OEIS

%I #6 Apr 23 2023 18:26:29

%S 1,0,0,0,-12,60,-570,3780,-29568,169344,-557160,-13049520,375064008,

%T -7823848032,135678667488,-2221166656800,32120158935552,

%U -397914002426496,2522488580207424,61215640433391744

%N Expansion of e.g.f.: sech(arctanh(x)*log(x+1))=1-12/4!*x^4+60/5!*x^5-570/6!*x^6...

%t With[{nn=20},CoefficientList[Series[Sech[ArcTanh[x]Log[x+1]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Apr 23 2023 *)

%K sign

%O 0,5

%A Patrick Demichel (patrick.demichel(AT)hp.com)

%E Definition clarified by _Harvey P. Dale_, Apr 23 2023