Triangle read by rows: T(n,k) = binomial(2*n,2*k)*binomial(2*n-2*k,n-k)/(n+1-k) for 0<=k<=n.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =6a(5) =1a(6) =5a(7) =30a(8) =15a(9) =1a(10) =14a(11) =140a(12) =140a(13) =28a(14) =1a(15) =42a(16) =630a(17) =1050a(18) =420a(19) =45a(20) =1a(21) =132a(22) =2772a(23) =6930a(24) =4620a(25) =990a(26) =66a(27) =1a(28) =429a(29) =12012