Sudoku Players' Forum (clone)

Here is an example for infinite solution grid. Due to the symmetry it is likely toroidal but I'm too lazy to check.

Mathimagics wrote:did you actually try the standard puzzle with the adjacent-cells-differ rule, and then found that it was hard (or impossible) to get solution grids?

Or does having all diagonals with different digits mean that each cell has a different neighbour even without declaring it?
The solution grid could be so constrained that we may have only 1 solution grid and the isomorphs!

tarek

Per Tarek's request and as promised:

All diagonals must have distinct numbers (no duplicate)

Nice!