T(n,k)=Number of nXk zero-sum -2..2 arrays with rows and columns lexicographically nondecreasing.

Terms

a(0) =1a(1) =3a(2) =3a(3) =5a(4) =29a(5) =5a(6) =8a(7) =226a(8) =226a(9) =8a(10) =12a(11) =1454a(12) =9331a(13) =1454a(14) =12a(15) =18a(16) =7815a(17) =301432a(18) =301432a(19) =7815a(20) =18a(21) =24a(22) =36487a(23) =7798656a(24) =50432052a(25) =7798656a(26) =36487a(27) =24a(28) =33a(29) =151593