Expansion of exp(tan(x)/cos(x)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =6a(4) =21a(5) =112a(6) =717a(7) =4592a(8) =38857a(9) =318208a(10) =3158329a(11) =32169984a(12) =363525789a(13) =4399544320a(14) =56250039237a(15) =779244812288