O.g.f.: Sum_{n>=0} n^n * (1+n*x)^(3*n) * x^n/n! * exp(-n*x*(1+n*x)^3).
A218678
O.g.f.: Sum_{n>=0} n^n * (1+n*x)^(3*n) * x^n/n! * exp(-n*x*(1+n*x)^3).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =22a(4) =161a(5) =1321a(6) =12541a(7) =130383a(8) =1482875a(9) =18153076a(10) =237430711a(11) =3295833146a(12) =48274094584a(13) =742868875984
External references
- oeis: A218678