E.g.f.: exp( Sum_{n>=1} sigma(n,n) * x^(n^2) / n^n ).
A226890
E.g.f.: exp( Sum_{n>=1} sigma(n,n) * x^(n^2) / n^n ).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =31a(5) =151a(6) =451a(7) =1051a(8) =33601a(9) =663601a(10) =5187001a(11) =25905001a(12) =254322751a(13) =10408719751a(14) =128046088171a(15) =920598820051
External references
- oeis: A226890