Expansion of e.g.f.: cosh(log(1+x)/cosh(x)).

Terms

a(0) =1a(1) =0a(2) =1a(3) =-3a(4) =0a(5) =0a(6) =210a(7) =-1260a(8) =3752a(9) =-46872a(10) =690960a(11) =-6013920a(12) =58389672a(13) =-895065600a(14) =12888358392a(15) =-168411308520