A012763 - OEIS

%I #6 Aug 02 2018 17:29:41

%S 1,0,-1,3,-18,60,-60,-1890,31472,-319032,2369280,-6374280,-209401368,

%T 5594400240,-90523285944,1016295254520,-3922383447232,

%U -184920315173888,6878045401558272,-151394798389814208

%N Expansion of e.g.f.: sech(cosh(x)*log(x+1))=1-1/2!*x^2+3/3!*x^3-18/4!*x^4+60/5!*x^5...

%t With[{nn=20},CoefficientList[Series[Sech[Cosh[x]Log[x+1]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Aug 02 2018 *)

%K sign

%O 0,4

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

%E Definition clarified by _Harvey P. Dale_, Aug 02 2018