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

Terms

a(0) =0a(1) =1a(2) =0a(3) =-2a(4) =12a(5) =-40a(6) =120a(7) =208a(8) =-6048a(9) =64640a(10) =-428160a(11) =986368a(12) =29812992a(13) =-652487680a(14) =8332047360a(15) =-60911593472a(16) =-293043130368