a(n) = Sum_{k=0..n} 2^k * binomial(n,k) * binomial(3*n+1,k).
A388045
a(n) = Sum_{k=0..n} 2^k * binomial(n,k) * binomial(3*n+1,k).
Terms
- a(0) =1a(1) =9a(2) =113a(3) =1561a(4) =22569a(5) =335137a(6) =5064793a(7) =77500017a(8) =1196924561a(9) =18618616249a(10) =291280485825
External references
- oeis: A388045