Tag Archives: almost nice loop

Stephens Extremes Snapshots I


Here we have highlight snapshots from the review puzzles from Paul Stephens’ Extreme collection.  Recent posts have been about the Stephens approach to basic and advanced solving.  The Sysudoku solving of two of the review puzzles, Weeks 48 and Addicts … Continue reading

Posted in Advanced Solving, Puzzle Reviews | Tagged , , , , , | Leave a comment

To Nishio or Not to Nishio


This post examines Paul  Stephens’ favored form of Nishio, from his two current books on advanced Sudoku solving.  The analysis of the Addicts 140 determines the relationship between Stephens’Nishio and a simple test for grouped almost nice eliminating loops on … Continue reading

Posted in Advanced Solving, Expert Reviews, Stephens | Tagged , , , , , | Leave a comment

Cell Forcing Chains


Here we examine forcing chains starting from all candidates in a cell.  When the number of chains is 2, there is nothing new.  Above that,  there is a new strategy to explore, which rivals LPO in complexity, but falls behind … Continue reading

Posted in Advanced Solving, Expert Reviews, Stuart | Tagged , , , , , | Leave a comment

Nishio Forcing Chains?


 Resuming the series on forcing chains, this post reveals that the Nishio forcing chain introduced on Andrew Stuart’s sudokuwiki site  is yet another re-interpretation of the AIC toxic set, a.k.a. the eliminating almost nice loop(ANL).  Here we also assert that … Continue reading

Posted in Advanced Solving, Expert Reviews, Stuart | Tagged , , , | 2 Comments

A Colorful AIC Feast


We are met today to confirm the AIC take down by sysudokie readers on a tough steer,  Megastar Maestro 49 of Fall 2009. The rodeo begins with limited coloring, the identification of five AIC hinge cells, and an extension of … Continue reading

Posted in Advanced Solving | Tagged , , , , | 2 Comments

Alternate Inference Chains (AIC)


Readers of this blog are familiar with an alternate inference chain in the form of an XY-chain on a bv map, or an xyt-chain on the grid, or as an X-chain or grouped X-chain on an X-panel.  Humans, as opposed … Continue reading

Posted in Advanced Solving | Tagged , , , | 3 Comments

The Shameless Sashimi


Which Sashimi did you find in the LA Times 5/14/09 5-panel?  Was this one of them?  We could describe it as a Sashimi 5-wing in r13 with fin r3c1.  Note the new 5-chain added to the panel.  It also removes … Continue reading

Posted in Advanced Solving | Tagged , , , , , | 2 Comments