G.f.: exp( Sum_{n>=1} A188202(n)*x^n/n ) where A188202(n) = [x^n] (1 + 2^n*x + x^2)^n.
A188203
G.f.: exp( Sum_{n>=1} A188202(n)*x^n/n ) where A188202(n) = [x^n] (1 + 2^n*x + x^2)^n.
Terms
- a(0) =1a(1) =2a(2) =11a(3) =206a(4) =17586a(5) =6878604a(6) =11551087875
External references
- oeis: A188203