Category Archives: Uncategorized

An AndrewsMcMeel  6-Star Sample 4-fills Out

Posted on June 28, 2022 by Sudent

Scroll back for the givens grid. After the fourth 4-fill, we never get back to the three unresolved 3-fills in the bypass trace. Here is the grid, just before SE6 (halfway down) wipes out the naked pairs. The Sysudoku basic … Continue reading →

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A Harder Kampbelmann, Barely Basic

Posted on May 31, 2022 by Sudent

Hard 143 starts with a stingy bypass, and requires box marking and some line marking. In the bypass, a r9 3-fill resolves  into SW8and the naked pair 36. W8 then follows, either from the 8’s dublex, or  from the West … Continue reading →

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Naked Pairs Carry the Ball in Hard 134

Posted on May 24, 2022 by Sudent

A second Kampbelmann Hard is tough on paper, but  gives way routinely to a systematic bypass. Here is the grid well into the bypass, with a large number of cells held in reserve by box filling naked pairs. In the … Continue reading →

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Recycle AIC Building on UHC 311

Posted on February 16, 2021 by Sudent

This post shows how the AIC building done by the review solvers on ultrahardcore 311 can be systematically duplicated by a human solver. The technique is a graphic one, very amenable to ©PowerPoint graphics, and slink marking of Sysudoku Basic. … Continue reading →

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Cluster Maintenance Pays in Nakamoto Extreme 23

Posted on January 28, 2020 by Sudent

In this post, a cluster wrap interrupts the Sudokuwiki march on Nakamoto Extreme 23, with an abrupt collapse. The following post then follows the original solution through to another example of Andrew Stuart’s “digit forcing chain”, to note that human … Continue reading →

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PencilPress Bottom Right 9 and Bean VI-24

Posted on July 23, 2019 by Sudent

PencilPress  500+ Sudoku Extreme Puzzles rates in Sysudoku as basic level, with most of the preselected puzzle on the bottom right corner of pages 9, 16, . . ., being solved in the bypass. In each of the posts verifying … Continue reading →

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Classic Review Ends,OnEx 261 Escapes Trials

Posted on April 30, 2019 by Sudent

This post traces the bypass finish of Classic 240 and presents the review table for James Forest’s Classic Sudoku. Then it continues the update review of Manuel Castillo’s Only Extreme Sudoku with Only Extreme 261. Demonstrating a solution without trial, … Continue reading →

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A Classic Insane 144

Posted on March 26, 2019 by Sudent

After the two Basic level 96 and 120, James Forest’s Classic Sudoku comes back with one puzzle, 144,  in the tradition of the KrazyDad Insane collection.  The bv are there, but it takes a few X-chain ANL to jar loose … Continue reading →

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KD Insane 485 Introduces the ALS Boomerang

Posted on January 29, 2019 by Sudent

This post is about the update of the 9/24/13 post on KrazyDad Insane v4, b8, n5. An unrecognized type of ANL found by Andrew Stuart’s Sudokuwiki solver is accorded a spotting technique, and a name suggesting the technique. When the … Continue reading →

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KD Insane 415 Updated

Posted on December 11, 2018 by Sudent

This post tells the story in the solving of Krazy Dad Insane v4, b1, n5, as reported in updated Sysudoku posts of 7/13/13 and 7/20/13. It’s one way that coloring and pattern analysis work together. Important features of Sysudoku Basic … Continue reading →

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