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

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

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

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

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

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

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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The ALS Node in the AIC

This post explains how an Almost Locked Set, an ALS, can be a node in an AIC, providing a slink between two winks connecting candidates of different numbers. In this blog the ALS was first applied in the Sysudoku version … Continue reading

Dessert at the Colorful AIC Feast

Happy 4th!  Last post, on Maestro 49 of Fall 2009 we mixed coloring and AIC to good effect, and discovered the joys of the slink/wink color shortcut in AIC chains. We continue now with two clusters. The second, red/orange cluster … Continue reading