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

A388912

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

Terms

    a(0) =1a(1) =6a(2) =56a(3) =594a(4) =6652a(5) =76776a(6) =903416a(7) =10774308a(8) =129775388a(9) =1575057960a(10) =19231572576a(11) =235968734106

External references