a(n) = [x^(n+1)*y] exp( Sum_{m>=1} (3^m + y)^m * x^m/m ), in which the coefficients of x^n*y^k are integer for n>=k>=0.
A155813
a(n) = [x^(n+1)*y] exp( Sum_{m>=1} (3^m + y)^m * x^m/m ), in which the coefficients of x^n*y^k are integer for n>=k>=0.
Terms
- a(0) =1a(1) =12a(2) =801a(3) =540720a(4) =3499254081
External references
- oeis: A155813