Expansion of e.g.f. cosh(arcsin(tanh(x))) (even powers only).

A012131

Expansion of e.g.f. cosh(arcsin(tanh(x))) (even powers only).

Terms

    a(0) =1a(1) =1a(2) =-3a(3) =21a(4) =-263a(5) =4841a(6) =-99723a(7) =-199939a(8) =501445617a(9) =-101818966319

External references