Tag Archives: irregular XYZ

Berthier’s xyt-chains in THLS


Next we review the introduction of xyt-chains in The Hidden Logic of Sudoku. These are modified XY-chains which allow extra candidates in the chain cells, and unlike regular XY-chains, make eliminations regardless of whether the chain starting candidate is true … Continue reading

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Insane 425 Introduces the Boomerang


This post checkpoints a stunning XYZ finish on Insane 415 and demonstrates a cluster merge by LPO with Insane 425, as part of a review of KrazyDad’s Insane collection on http://www.krazydad.com .  A spotting technique is explained and named for a type of … Continue reading

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