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ExpertChains and uniqueness

Practise: Nice Loop

Follow the marked loop back to its start. Which candidate returns through two weak links and therefore cannot stay?

This direct drill starts on a verified Nice Loop. Trace the prepared candidates around the loop; it removes a note and does not place a digit yet.

Example 1 of 4

Practice
Mistakes0Hints0Score3,500Time0:00

Your turn first

Your turn first

Trace the marked loop. Which prepared 5-note appears at both ends of the two weak closing links?

Remember

A weak-discontinuity Nice Loop returns to one candidate through two weak links. That candidate cannot be true, so remove it without placing a digit yet.

Put it to use

Where you will meet it

Expert grids are the only place this pattern regularly decides the solve. Bring your notes.

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