G.f.: Sum_{n>=0} (4*n+1)^n * x^n / (1 + (4*n+1)*x)^n.
A221160
G.f.: Sum_{n>=0} (4*n+1)^n * x^n / (1 + (4*n+1)*x)^n.
Terms
- a(0) =1a(1) =5a(2) =56a(3) =864a(4) =16896a(5) =399360a(6) =11059200a(7) =350945280a(8) =12551454720a(9) =499415777280
External references
- oeis: A221160