a(n) = [x^n] exp(Sum_{k>=1} (-1)^(k+1)*x^k/(k*(1 - n*x^k))).
A305209
a(n) = [x^n] exp(Sum_{k>=1} (-1)^(k+1)*x^k/(k*(1 - n*x^k))).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =12a(4) =86a(5) =885a(6) =11234a(7) =172711a(8) =3112262a(9) =64422126a(10) =1506406702a(11) =39279802969
External references
- oeis: A305209