Expansion of e.g.f. Sum_{k>=1} (sec(x^k) - 1) (even powers only).

A330528

Expansion of e.g.f. Sum_{k>=1} (sec(x^k) - 1) (even powers only).

Terms

    a(0) =1a(1) =17a(2) =421a(3) =29945a(4) =1864921a(5) =382577645a(6) =43788506581

External references