a(n) = Sum_{k = 0..n} 4^(n-k)*binomial(n,k)*binomial(n-1,k)*binomial(2*k,k).

A362676

a(n) = Sum_{k = 0..n} 4^(n-k)*binomial(n,k)*binomial(n-1,k)*binomial(2*k,k).

Terms

    a(0) =1a(1) =4a(2) =32a(3) =328a(4) =3840a(5) =48504a(6) =641984a(7) =8765712a(8) =122370048a(9) =1736921560a(10) =24975268032a(11) =362872728816

External references