Expansion of e.g.f. log(sech(x) + sin(x)).

Terms

a(0) =0a(1) =1a(2) =-2a(3) =4a(4) =-12a(5) =60a(6) =-392a(7) =2784a(8) =-23072a(9) =225680a(10) =-2475392a(11) =29884864a(12) =-397554432a(13) =5784292800a(14) =-91112993792