a(n) = Sum_{k=0..n} 3^k * binomial(n,k) * binomial(2*n+1,k).
A388048
a(n) = Sum_{k=0..n} 3^k * binomial(n,k) * binomial(2*n+1,k).
Terms
- a(0) =1a(1) =10a(2) =121a(3) =1576a(4) =21331a(5) =295582a(6) =4161340a(7) =59258080a(8) =851142775a(9) =12307759030a(10) =178937264089
External references
- oeis: A388048