G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^3 * 3^k ).
A206179
G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^3 * 3^k ).
Terms
- a(0) =1a(1) =4a(2) =25a(3) =196a(4) =1747a(5) =16996a(6) =175936a(7) =1907224a(8) =21423385a(9) =247515796a(10) =2925668236a(11) =35239199704a(12) =431207470105
External references
- oeis: A206179