Category Archives: Extreme Solving

Extraordinary techniques deferred past advanced ones, because of effort vs. likelihood of success.

The Elbow n-set of shye’s Roman Candle

Posted on February 1, 2022 by Sudent

This post is about the sixth example of forum commentator shye’s introductory post on fireworks, his name for elimination methods based on the restriction of candidate values in row/box/column combinations. Our series of posts on fireworks defines a particular form … Continue reading →

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Sharing Hanabi’s Secrets

Posted on January 18, 2022 by Sudent

This post details a fireworks analysis on “Hanabi”, shye’s fifth example. The first four examples used matching elbows alone, along with bi-value cells. This one uses forcing chains to identify the value winning placement in the neck cell shared by … Continue reading →

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Fireworks 4 Stretches the Matched Elbow Rule.

Posted on January 11, 2022 by Sudent

After a challenging basic, we get two matched pairs on two values again, but this time, linked by a single bv. The second challenge is the application of the matched elbow rule of the last post in a more hypothetical … Continue reading →

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An AIC Parade by ultrahardcore 397

Posted on December 14, 2021 by Sudent

This post follows basic with a variety of Alternate Inference Chains. It is an opportunity to compare their effects and corresponding Sysudoku labeling. Three bypass clues, naked triple eliminations, and the line slinks marked in cell corners, that’s the  outcome … Continue reading →

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The Complex 1-Way in AIC Building

Posted on May 11, 2021 by Sudent

This post is about an AIC building option offered by Philip Beeby’s PhilsFolly.com solver, and how and where it is best applied in DIY solving.  Here we refer to this solver as Beeby and this technique as complex 1-way.  Complex … Continue reading →

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Ultrahardcore Review ALS-wings V

Posted on May 4, 2021 by Sudent

This post completes a survey of ALS-wings in the review of Stefan Heine’s ultrahardcore collection. The study was to determine how ALS-wings can be constructed as ALS maps are built. This post covers five more examples in UHC 443 found … Continue reading →

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Ultrahardcore Review ALS-wings IV

Posted on April 27, 2021 by Sudent

The survey of ALS-wings in the ultrahardcore review continues, with new wing building situations, another ALS version of the Death Blossom, and an amazing ALS. In this UHC 267 ALS-wing it’s a two box ALS , connected by a column … Continue reading →

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Building the ALS-wings of UHC 3

Posted on April 6, 2021 by Sudent

This post begins a review of examples of ALS-wings from the ultrahardcore review. The review will illustrate a DIY strategy for constructing them, that is compatible with the concurrent ALS mapping and ALS_XZ building processes of the previous posts. Ultrahardcore … Continue reading →

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An ALS_XZ Wrap Up of UHC 311

Posted on March 30, 2021 by Sudent

This post shows what it means to maintain three three ALS maps. ALS map updates are followed through a series of  ALS_XZ until a decisive coloring wrap on Stefan Heine’s ultrahardcore 311. We are exploring ALS mapping as ALS_XZ scans … Continue reading →

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Scanning the Column ALS and Some ALS Coloring

Posted on March 16, 2021 by Sudent

This post displays the column and box ALS maps, and scans for AIC the columns. The box scans are started, but get interrupted by an ALS coloring expansion. We start with the ALS column map on ultrahardcore 311 . It … Continue reading →

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