Category Archives: Heine

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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Ultrahardcore Review ALS-wings II


The  ultrahardcore ALS-wing survey continues with examples from UHC 47. The survey illustrates how ALS-wings are found as ALS are added to ALS maps. Continuing the survey into a second review puzzle UHC 47, the reward is this well laid … Continue reading

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Continuing the Box ALS Scans for UHC 311


This post continues with the box to box, row and column scans for ALS_XZ.  The C and S ALS fit into one red/orange cluster with a trap. The clusters meet in cell r7c8, showing that blue or orange or both … 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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An Error Hides a Lite Coloring Trap on ultrahardcore 399


This post corrects an error on the post of December 8, that prevents a lite coloring trap in ultrahardcore 399. Then there’s follow up on the trap, with the lite coloring marking in place. Trial is not avoided, but the … Continue reading

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Pattern Trials Peel the UHC 487 Onion


The ultrahardcore review ends, with Stefan Heine’s 487 giving up a naked single and two skyscrapers, and a jaw dropping complex 1-way, shuts down the solver team. Slicing at it with three onion peeling pattern trials leaves very little for … Continue reading

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SASdC Unlock UHC 443 for Beeby


After the hidden unique rectangle hinted last week, a pair of Single Alternate Sue de Coq trials gets the review solver Beeby moving again. ALS-wings and a finned X-wing get us to a colorful finish. The hidden unique rectangle left … Continue reading

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Beeby Softens Up ultrahardcore 443


This post reports a series of Beeby ALS-XZ featuring alignments in Z and X, almost to the point where a trial is needed. A simple basic trace means a hard start, with a crowded grid. Sudokuwiki’s 579-wing is a Beeby … Continue reading

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