a(n) = 4^(2*n) * (n!)^3 * (n+1)!.A280100a(n) = 4^(2*n) * (n!)^3 * (n+1)!.Terms a(0) =1a(1) =32a(2) =12288a(3) =21233664a(4) =108716359680External referencesoeis: A280100