Number of lower triangles of an n X n -3..3 array with all row and column sums zero.
A195517
Number of lower triangles of an n X n -3..3 array with all row and column sums zero.
Terms
- a(0) =1a(1) =1a(2) =7a(3) =175a(4) =27267a(5) =23663523a(6) =122092290831
External references
- oeis: A195517