a(n) = Sum_{k=0..n} 2^k * 3^(n-k) * binomial(2*n+1,k) * binomial(2*n-k,n-k).

A385669

a(n) = Sum_{k=0..n} 2^k * 3^(n-k) * binomial(2*n+1,k) * binomial(2*n-k,n-k).

Terms

    a(0) =1a(1) =12a(2) =184a(3) =3088a(4) =54216a(5) =977712a(6) =17946384a(7) =333571488a(8) =6258363016a(9) =118270099312

External references