Expansion of e.g.f. sech(x*exp(x)).

Terms

a(0) =1a(1) =0a(2) =-1a(3) =-6a(4) =-19a(5) =20a(6) =899a(7) =7966a(8) =27705a(9) =-366552a(10) =-8374201a(11) =-80690302a(12) =9794597a(13) =16015845820a(14) =317370642315