a(n) = coefficient of x^n in the (2^(n-1))-th iteration of x+x^2 for n>=1.
A158261
a(n) = coefficient of x^n in the (2^(n-1))-th iteration of x+x^2 for n>=1.
Terms
- a(0) =1a(1) =2a(2) =12a(3) =364a(4) =49280a(5) =27297360a(6) =59855127360
External references
- oeis: A158261