a(n) = Sum_{k=0..n} 2^k * 3^(n-k) * binomial(3*n+1,k) * binomial(3*n-k,n-k).
A385670
a(n) = Sum_{k=0..n} 2^k * 3^(n-k) * binomial(3*n+1,k) * binomial(3*n-k,n-k).
Terms
- a(0) =1a(1) =17a(2) =429a(3) =12048a(4) =355501a(5) =10792737a(6) =333781044a(7) =10457735928a(8) =330823760061
External references
- oeis: A385670