Triangle T(n, k) = 2*(-1 + 2*k)*T(n-1, k) - T(n-2, k) with T(-2, k) = T(-1, k) = 1, read by rows.

Terms

a(0) =-3a(1) =5a(2) =1a(3) =-7a(4) =1a(5) =169a(6) =9a(7) =1a(8) =985a(9) =8721a(10) =-11a(11) =1a(12) =5741a(13) =86329a(14) =489061a(15) =13a(16) =1a(17) =33461a(18) =854569a(19) =6811741a(20) =31622993a(21) =-15a(22) =1a(23) =195025a(24) =8459361a(25) =94875313a(26) =567451585a(27) =2351330961a(28) =17a(29) =1