Monthly Archives: May 2015

A Tracing Exercise with Wex 434


A careful marking session finishes Wex 434 in box marking! This surprising event demonstrates how 2-D depth first tracing fully exploits removals and confirmations. My first time through to a solution I considered Wex 434 among the most deserving of … Continue reading

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Two More Wex Join Sue’s Parade


In Weekly Extreme 432, a Sue de Coq shows some promising removals, but we never get there, because the verification trial solves the puzzle. After moderate basic solving in all three Sysudoku stages,     Wex 432 presents the Sue … Continue reading

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Wex 431 Slips by Sue, but is Caught


Finally a Weekly Extreme gets through the Sue de Coq gauntlet. Or so I thought. But after a joyful romp into XYZ-wing technique, and coloring aided by pattern analysis, I get to demonstrate instead another resource of my single alternative … Continue reading

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Gordon Fick Tricks More Extreme 200


This post reports an alternative solution, without my pattern analysis, to Antoine Alary’s special More Extreme 200, based on a Sysudoku reader’s innovative use of a little known technique, the double common ALS pair. Two ALS sharing two restricted common … Continue reading

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