Number of lower triangles of an n X n -6..6 array with all row and column sums zero.

A195520

Number of lower triangles of an n X n -6..6 array with all row and column sums zero.

Terms

    a(0) =1a(1) =1a(2) =13a(3) =1105a(4) =1089411a(5) =11131321791

External references