T(n,k)=Number of -k..k arrays x(0..n-1) of n elements with zero sum and no two neighbors equal.

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =4a(5) =6a(6) =1a(7) =6a(8) =14a(9) =8a(10) =1a(11) =8a(12) =32a(13) =52a(14) =14a(15) =1a(16) =10a(17) =52a(18) =168a(19) =200a(20) =32a(21) =1a(22) =12a(23) =82a(24) =380a(25) =892a(26) =708a(27) =56a(28) =1a(29) =14