Triangle T(n, k) = A060821(n,k) + A060821(n,n-k), read by rows.

Terms

a(0) =2a(1) =2a(2) =2a(3) =2a(4) =0a(5) =2a(6) =8a(7) =-12a(8) =-12a(9) =8a(10) =28a(11) =0a(12) =-96a(13) =0a(14) =28a(15) =32a(16) =120a(17) =-160a(18) =-160a(19) =120a(20) =32a(21) =-56a(22) =0a(23) =240a(24) =0a(25) =240a(26) =0a(27) =-56a(28) =128a(29) =-1680