Squares of Catalan numbers.

Terms

a(0) =1a(1) =1a(2) =4a(3) =25a(4) =196a(5) =1764a(6) =17424a(7) =184041a(8) =2044900a(9) =23639044a(10) =282105616a(11) =3455793796a(12) =43268992144a(13) =551900410000