Monthly Archives: July 2020

Ultrahardcore 47 Pattern Trial

Posted on July 28, 2020 by Sudent

This post bypasses Sudokuwiki’s  forcing chain parade with a value pattern trial, strengthened by the Single Alternate Sue de Coq analysis of the last post.  One pattern is tried and fails, leaving a coloring cluster. When the trial of the … Continue reading →

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Ultrahardcore 47 Single Alternate SdC Trials

Posted on July 21, 2020 by Sudent

This post does the basics on the second Stefan Heine ultrahardcore right page under review.  Then it shows eight ways to do the five advanced moves up to forcing chains, two of them duplicated by boomerangs. It closes by  identifying … Continue reading →

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Beeby on Heine’s ultrahardcore 3

Posted on July 14, 2020 by Sudent

This post highlights several moves from Phillip Beeby’s solver, which are alternatives to those appearing in the five earlier posts on Stefan Heine’s ultrahardcore 3. One result is a solution without the second blue green trial, left as a project … Continue reading →

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Readers Solve Ultrahardcore 3

Posted on July 7, 2020 by Sudent

This post returns to the Stefan Heine’s utrahardcore  3 solution path just before cell and unit forcing chains. It turns out that an immediate coloring trial reaches a solution without them. Then we report how two Sysudoku readers solve it … Continue reading →

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