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SOLO-008 · Irregular Sudoku

EXTREME

The Nine Territories

Complete the grid completely. Only one solution respects all constraints.

Materials: Pencil and gum; no commercial material.

Rules you need

The puzzle

The empty boxes are to be completed. The given numbers are fixed. The answer and proof are on another page.

Coordinates: lines from top to bottom, columns from left to right.
L / C123456789
17
2963
331
43487
5
682
725
8538
9194
Why this level?

After single candidates, single places, bare pairs/triples and interactions between units, the solver still reaches bifurcations. The exhaustive evidence reaches 8 intertwined hypotheses, examines 27 states and closes 13 branches by contradiction. The Extreme level combines eliminations of candidates and deep branched analysis; this is not a ranking based on the number of empty boxes. Editorial evaluation according to the protocol of the collection, without calibration on a panel of players; another logical path can be made to the extent that it is possible to determine the number of empty boxes. be shorter.

Your workspace

Write down your assumptions separately from deductions you have proved.