Triangle read by rows: T(n, k) = 2^n*Sum_{j=0..k} (-1)^(k - j)*binomial(k, j)* Pochhammer(j/2, n).

Terms

a(0) =1a(1) =0a(2) =1a(3) =0a(4) =3a(5) =2a(6) =0a(7) =15a(8) =18a(9) =6a(10) =0a(11) =105a(12) =174a(13) =108a(14) =24a(15) =0a(16) =945a(17) =1950a(18) =1710a(19) =720a(20) =120a(21) =0a(22) =10395a(23) =25290a(24) =28080a(25) =16920a(26) =5400a(27) =720a(28) =0a(29) =135135