Tag Archives: cell forcing chains

Cell and Unit Forcing Begins in Ultrahardcore 3


This post reveals yet another way to start a boomerang, and reconsiders the practicality of Andrew Stuart’s Cell  and Unit Forcing Chains, this time facing an ultrahardcore right page. We get to a choice between Sudokuwiki and a coloring trial … Continue reading

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Sudokuwiki Ends Nakex 63 On Its Own


This post picks up on the Sudokuwiki/Sysudoku resolution of Nakamoto Extreme 63 where it was overtaken by pattern analysis and coloring, and finishes it in two ways, one humanly practical and one not. Sudokuwiki doesn’t maintain coloring clusters between moves, … Continue reading

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Insane 475 by Sudokuwiki and SASdC


In the updated review of the KrazyDad collection of puzzles, Andrew Stuart’s Sudokuwiki solver is a backup on advanced solving, except in irregular XYZ, coloring, pattern analysis, and trials. Prior to the update on Sysudoku review of Insane 475 in … Continue reading

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Higher Rank Theory


This post extends the proof of the rank theorem to the rank = r >0 case, and finds a sysudoku interpretation of a rank 3 removal from the General Logic page of http://www.SudokuOne.com .  The method is Andrew Stuart’s cell … Continue reading

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ALS Merged Cell Forcing Chains


This post demonstrates the merger of cell forcing chains by means of ALS nodes.  I  checkpoint  three triple cell forcing chains from the challenge of the previous post, and argue that comprehensive search for cell forcing chains beyond the dual level … Continue reading

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Cell Forcing Chains


Here we examine forcing chains starting from all candidates in a cell.  When the number of chains is 2, there is nothing new.  Above that,  there is a new strategy to explore, which rivals LPO in complexity, but falls behind … Continue reading

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