Sudoku HowTo

Locked Set

For a set of cells in the same unit that contain a group of candidates, when the number of cells in the set and the number of candidates in the group is the same, the set of cells is considered a Locked Set.

A Locked Set has the following properties -
  • 1. The cells in the set will end up containing one of the group of candidates.
  • 2. The candidates in the group cannot be used in other cells in the unit because they will all be used in the cells in the set.
A Naked Pair is an example of a locked set.

An Almost Locked Set is a set of cells in the same unit where the number of candidates in the set is one more than the number of cells.
The blue cells in Figure 1 are an example of a Locked Set in box 2 using the candidates 1 and 6.
The blue cells in Figure 2 are a Locked Set in row 6 using the candidates 3, 4 and 9.

10 December 2014
by John
RE: Comments and feedback for lockedSet

There is a page with multiple examples of almost locked sets in the How To section
9 December 2014
by Jason McCreary
RE: Comments and feedback for lockedSet

Can you provide an example figure of the Almost Lock Set.

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This page last updated on February 5, 2015