Number of 13 X 13 arrays of squares of integers, symmetric under 90-degree rotation, with all rows summing to n.
A156415
Number of 13 X 13 arrays of squares of integers, symmetric under 90-degree rotation, with all rows summing to n.
Terms
- a(0) =1a(1) =120a(2) =0a(3) =0a(4) =14564760a(5) =66083040a(6) =0a(7) =0a(8) =2511725250a(9) =3360660500a(10) =0a(11) =0a(12) =105602337600a(13) =192407274081a(14) =0a(15) =0a(18) =0a(19) =0
External references
- oeis: A156415