Number of nX4 zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing.

A202029

Number of nX4 zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing.

Terms

    a(0) =3a(1) =56a(2) =1341a(3) =29363a(4) =537572a(5) =8249505a(6) =108479344a(7) =1248911674a(8) =12812139620a(9) =118772002152

External references