G.f. A(x) satisfies A(A(A(A(A(x))))) = Sum_{k>=1} k * 25^(k-1) * x^k.
A372520
G.f. A(x) satisfies A(A(A(A(A(x))))) = Sum_{k>=1} k * 25^(k-1) * x^k.
Terms
- a(0) =0a(1) =1a(2) =10a(3) =-25a(4) =1000a(5) =-18125a(6) =131250a(7) =11609375a(8) =-630156250a(9) =4314062500
External references
- oeis: A372520