A013051 - OEIS

%I #10 May 11 2022 19:09:01

%S 2,-13,289,-13039,1003825,-118036631,19683093369,-4418337316175,

%T 1284612873046753,-469616483548721575,210832414586400163561,

%U -114033567896612568885023,73135588741410223752308241,-54879566868084569212176674615,47633391630419948548873776142041

%N Expansion of e.g.f. tanh(sinh(x)+tan(x)) (odd powers only).

%e 2*x-13/3!*x^3+289/5!*x^5-13039/7!*x^7...

%t With[{nn=30},Take[CoefficientList[Series[Tanh[Sinh[x]+Tan[x]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* _Harvey P. Dale_, May 11 2022 *)

%o (PARI) my(x='x + O('x^40), v=Vec(serlaplace(tanh(sinh(x)+tan(x))))); vector(#v\2, k, v[2*k-1]) \\ _Michel Marcus_, Jun 20 2020

%K sign

%O 1,1

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

%E More terms from _Michel Marcus_, Jun 20 2020