Category Archives: Extreme Solving

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

Sharing Hanabi’s Secrets


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.


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


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


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


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


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


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


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


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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Building ALS Maps With Suset Tables


This post displays the ALS map for rows of UHC 311, at the moment when the Beeby solver returned the first ALS_XZ. The suset ALS marking and building aid is introduced, and suset tables for rows, columns and boxes are … Continue reading

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