Expansion of cosh(x)/cos(sin(x)).

A009181

Expansion of cosh(x)/cos(sin(x)).

Terms

    a(0) =1a(1) =2a(2) =8a(3) =8a(4) =-960a(5) =-22400a(6) =251008a(7) =53882624a(8) =2088660992a(9) =-173107810304

External references