Sudoku in Sudoku — Hard Version
(Published on 3. January 2026, 13:23 by Kutsumi Hane)
Rules:
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·Disjoint Groups:
Here you can solve the puzzle online: Solve on SudokuPad
The difficulty is probably 4-5 stars. I wish you joyful solving! (See also Easy Version)
Hint:
| · | The solve involves symbolic reasoning with letter variables rather than direct numeric deduction. |
| · |
All 3×3 Magic Squares form a single orbit under the Dihedral Group (D4). Check whether the Magic Squares formed by the numbers in Quadruples/Doubles and Box 5 are equivalent under rotations of D4. |
Solution code: Digits in the center of each box, listed from Box 1 to Box 9.
Comments
on 3. January 2026, 16:49 by Rollo
I can't see any difference between this and the easy version.
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Response from Kutsumi Hane:
Thanks for your comment and for taking the time to compare the two versions - much appreciated, and happy solving. You are right that both versions lead to the same final solution. However, the Hard version removes one given constraint - the "No Triple Evens" rule.
In the Easy version, this rule allows certain branches in the solving path to be ruled out very quickly, because sequences of three even digits can be eliminated immediately. In the Hard version, without that constraint, these branches are no longer pruned automatically; the solver must carry the reasoning further — unless one proceeds by brute-force trial-and-error guessing. This makes the logical path less direct and therefore increases the difficulty.
So the puzzle content and final solution are identical, but the intended solving experience is different.
on 3. January 2026, 15:03 by Kutsumi Hane
Modified the Solution Code requirements;
Difficulty adjusted to 4 stars.
