Tag Archives: AIC

No THLS Case for Hidden XY Chains


This post and the next demonstrate that the examples presented in The Hidden Logic of Sudoku as requiring “Hidden” XY Chains actually have alternative, and much less demanding, resolution paths in the Sysudoku repertoire.  The burdensome maintenance of symmetry grids is … Continue reading

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Hodoku Nice Loop Mythology


This post dismisses the Stephens/Hobiger theory of cell links, propogation rules, and loop closing rules as unnecessary and overcomplicated. It uses the first two Hodoku AIC ANL examples to demonstrate the alternative Sysudoku chain construction process. As a blogger, one … Continue reading

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Hodoku Chain Building


This post endorses Hodoku’s explanation of strong and weak links, regretfully confined to chains. His discussions of grouping and ALS nodes are supplemented for completeness. Hodoku graphic representation of chains by cell shading and candidate coloring is seen to be … Continue reading

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Decoding Hodoku Chain Notes


This post comments on the first part of the Hodoku “Chains and Loops” page. It reveals the premise dependent view of chains to be based on computer coding, and unsuited for human solving advice. It explains Hodoku’s chain notations as … Continue reading

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A Sudokuwiki Resolution of Insane 475


In this post Insane 475 is taken through basic and then submitted to Andrew Stuart’s Sudokuwiki solver for advanced solving.  In the original review, the puzzle was solved by an Single Alternative Sue de Coq trial, but in this update … Continue reading

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Digit Forcing Chains?


Is Andrew Stuart’s Digit Forcing Chains a useful new solving technique? Actually, no.  Andrew’s  sudowiki site introduces digit forcing chains with examples that raise – and seem to settle – that question. Needless confusion is created by this unwarranted introduction. First, have you … Continue reading

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Toxic ALS in Unsolvable 40


Our struggle with Unsolvable 40 continues with a detailed walk through of the search for ALS toxic sets, and an analysis of the its stuck number ALS. Here is our grid with row ALS superimposed on a thin, as yet … Continue reading

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