a(n) = Catalan(n)^2*(4n + 1).

Terms

a(0) =1a(1) =5a(2) =36a(3) =325a(4) =3332a(5) =37044a(6) =435600a(7) =5337189a(8) =67481700a(9) =874644628a(10) =11566330256a(11) =155510720820