Expansion of e.g.f. exp(x*tanh(x)) (even powers only).
A009273
Expansion of e.g.f. exp(x*tanh(x)) (even powers only).
Terms
- a(0) =1a(1) =2a(2) =4a(3) =-24a(4) =400a(5) =-5600a(6) =-103872a(7) =26975872a(8) =-3438685952a(9) =417995260416
External references
- oeis: A009273