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SOLO-004 · Classic Sudoku

EXTREME

Branches of Silence

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
17284
2312
365
4
58572
696
78453
856
931
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 81 states and closes 40 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 by a single candidate, single places, bare pairs/triples and interactions between units. be shorter.

Your workspace

Write down your assumptions separately from deductions you have proved.