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Remote Pair

When matching two-candidate cells form a forcing chain.

Explanation

A Remote Pair connects cells that all contain the same two candidates. Along an even-length chain, the endpoints must split those two candidates, so any cell seeing both endpoints can remove both.

Remote Pair example Sudoku board 6 5 8 2 1 4 2 5 8 9 1 9 4 6 2 5 5 6 2 3 7 9 8 1 7 1 6 9 4 5 3 8 4 7 8 1 7 9 3 4 2 9 4 5 8 1 2 7 1 4 5 9 8
An example board where Remote Pair applies

Practice tip

First list all two-candidate cells. Group matching pairs, then trace links through rows, columns, or boxes.

Example steps

  1. Find several cells that all contain the same two candidates.
  2. Trace a linked chain where each neighboring pair shares one unit.
  3. Remove both candidates from cells that see both chain endpoints.

Try this technique on a real puzzle.

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