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SOLO-018 · Futoshiki

EXPERT

The Seven Staircases

Complete square 7 × 7 with figures from 1 to 7.

Materials: Pencil, gum and gridded paper; no commercial game required.

Rules you need

The puzzle

All useful inequalities are given below; the neighbourhoods not mentioned do not bear any additional constraints.

L5C1 < L4C1

L6C6 < L5C6

L3C6 < L3C7

L2C6 < L2C7

L6C2 < L7C2

L4C1 < L3C1

L7C7 < L7C6

L5C7 < L6C7

L5C2 < L4C2

L1C4 < L1C5

L1C4 < L2C4

L6C1 < L7C1

L6C4 < L7C4

L6C6 < L6C5

L4C2 < L3C2

L4C5 < L3C5

L2C7 < L3C7

Coordinates: lines from top to bottom, columns from left to right.
L / C1234567
1···2·5·
26···4··
3··3·5··
4···6···
5·······
6······7
7··5··63
Why this level?

The crossover of single lines, single columns and inequities is not closed by propagation of the only forced numbers in the reference solver. The Expert level is based on the combination of single terminals and locations, followed by controlled exploration; it is not only a result of the size of the square.

Your workspace

Write down your assumptions separately from deductions you have proved.