Expansion of e.g.f. sqrt(sec(sqrt(2)*x)), showing coefficients of only the even powers of x.

A126156

Expansion of e.g.f. sqrt(sec(sqrt(2)*x)), showing coefficients of only the even powers of x.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =139a(4) =5473a(5) =357721a(6) =34988647a(7) =4784061619a(8) =871335013633

External references