E.g.f. S(x) satisfies: C(x)^2 - S(x)^2 = 1 and C'(x)^2 + S'(x)^2 = 1, where C(x) is the e.g.f. of A290880.

A290881

E.g.f. S(x) satisfies: C(x)^2 - S(x)^2 = 1 and C'(x)^2 + S'(x)^2 = 1, where C(x) is the e.g.f. of A290880.

Terms

    a(0) =1a(1) =-1a(2) =25a(3) =-1705a(4) =227665a(5) =-50333425a(6) =16655398825

External references