Triangle T(n, m) = binomial(n+2, m)*binomial(n+2, n-m), read by rows.

Terms

a(0) =1a(1) =3a(2) =3a(3) =6a(4) =16a(5) =6a(6) =10a(7) =50a(8) =50a(9) =10a(10) =15a(11) =120a(12) =225a(13) =120a(14) =15a(15) =21a(16) =245a(17) =735a(18) =735a(19) =245a(20) =21a(21) =28a(22) =448a(23) =1960a(24) =3136a(25) =1960a(26) =448a(27) =28a(28) =36a(29) =756