Platon Sudoku · Sudoku Study

Grouped candidate nodes · Core Concepts

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

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Definition

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

How to find it

Fix a digit and find positions sharing both a line and a box.

Common mistake

Same-digit candidates scattered across boxes are not one intersection group.

Pair · Row

Teaching board · local candidate diagram

Observe candidates

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

Candidates 2 at r3c1, r3c2 share a line and box; G represents this group.

Verify the condition

Fix a digit and find positions sharing both a line and a box.

Candidates 2 at r3c1, r3c2 share a line and box; G represents this group.

Draw the conclusion

The marked candidates share a line-box intersection, so they can form one grouped node.

Candidates 2 at r3c1, r3c2 share a line and box; G represents this group.

G1: R3C1=2, R3C2=2

Pair · Column

Teaching board · local candidate diagram

Observe candidates

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

Candidates 2 at r1c3, r2c3 share a line and box; G represents this group.

Verify the condition

Fix a digit and find positions sharing both a line and a box.

Candidates 2 at r1c3, r2c3 share a line and box; G represents this group.

Draw the conclusion

The marked candidates share a line-box intersection, so they can form one grouped node.

Candidates 2 at r1c3, r2c3 share a line and box; G represents this group.

G1: R1C3=2, R2C3=2

Triple · Row

Teaching board · local candidate diagram

Observe candidates

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

Candidates 2 at r3c1, r3c2, r3c3 share a line and box; G represents this group.

Verify the condition

Fix a digit and find positions sharing both a line and a box.

Candidates 2 at r3c1, r3c2, r3c3 share a line and box; G represents this group.

Draw the conclusion

The marked candidates share a line-box intersection, so they can form one grouped node.

Candidates 2 at r3c1, r3c2, r3c3 share a line and box; G represents this group.

G1: R3C1=2, R3C2=2, R3C3=2

Triple · Column

Teaching board · local candidate diagram

Observe candidates

Candidates of one digit in a shared intersection can act as one logical node. A true group means at least one member is true.

Candidates 2 at r1c3, r2c3, r3c3 share a line and box; G represents this group.

Verify the condition

Fix a digit and find positions sharing both a line and a box.

Candidates 2 at r1c3, r2c3, r3c3 share a line and box; G represents this group.

Draw the conclusion

The marked candidates share a line-box intersection, so they can form one grouped node.

Candidates 2 at r1c3, r2c3, r3c3 share a line and box; G represents this group.

G1: R1C3=2, R2C3=2, R3C3=2