Triangle read by rows in which row n contains (2i)!*(2j)!/(i!*j!*(i+j)!) for i + j = n, i = 0..n.

Terms

a(0) =1a(1) =2a(2) =2a(3) =6a(4) =2a(5) =6a(6) =20a(7) =4a(8) =4a(9) =20a(10) =70a(11) =10a(12) =6a(13) =10a(14) =70a(15) =252a(16) =28a(17) =12a(18) =12a(19) =28a(20) =252a(21) =924a(22) =84a(23) =28a(24) =20a(25) =28a(26) =84a(27) =924a(28) =3432a(29) =264