Triangle read by rows: T(n, k) = Sum_{t=k..n-2} (-1)^(t-k)*(n-t)!*binomial(t,k)*binomial(n-2,t).

Terms

a(0) =2a(1) =4a(2) =2a(3) =14a(4) =8a(5) =2a(6) =64a(7) =42a(8) =12a(9) =2a(10) =362a(11) =256a(12) =84a(13) =16a(14) =2a(15) =2428a(16) =1810a(17) =640a(18) =140a(19) =20a(20) =2a(21) =18806a(22) =14568a(23) =5430a(24) =1280a(25) =210a(26) =24a(27) =2a(28) =165016a(29) =131642