Triangle read by rows, T(n, k) = [x^k] hypergeom([1/2, -n, -n], [1, 1], 4*x).

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =8a(5) =6a(6) =1a(7) =18a(8) =54a(9) =20a(10) =1a(11) =32a(12) =216a(13) =320a(14) =70a(15) =1a(16) =50a(17) =600a(18) =2000a(19) =1750a(20) =252a(21) =1a(22) =72a(23) =1350a(24) =8000a(25) =15750a(26) =9072a(27) =924a(28) =1a(29) =98