Category Archives: Advanced Solving

Techniques applying after candidates are identified. Why they work. How and when to look for them.

Mixed Solutions on Nakamoto Extreme 63


This post reports Sudokuwiki AIC building in Nakex 63, until it is overtaken by pattern analysis and coloring. The solver’s path is continued in the following post. Nakex 63 basic is tough, despite a productive bypass.     The first … Continue reading

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Nakamoto Extreme 43 Redefines Sysudoku Extreme


This post recounts another AIC building project of 15 boomerangs, Nakamoto Extreme 43. The Nakamoto Extreme collection justifies the ‘extreme’ label by possibly exhausting the time and patience of a human solver.  Let’s say, if a puzzle justifies a trial … Continue reading

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Cluster Maintenance Pays in Nakamoto Extreme 23


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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Nakamoto Extreme 3 Exits in Full Color


This post continues the Sysudoku report and supplemented Sudokuwiki solution of Nakex 3. We pick up from last week with matching  8 pairs in E and SE. The starting slink has been available since Sudokwiki entered AIC building, but new … Continue reading

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Reviewing a Truly Extreme Collection


This post and the next initiate a review of Sudoku Puzzle Book, Extreme Level by J. B. Nakamoto, with Nakex 3. The review combines moves by Andrew Stuart’s Sudokuwiki solver with Sysudoku alternatives, while reporting and interpreting moves in accordance … Continue reading

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Super Fiendish Bookends 67 and 77


This post steps through the most fiendish of the 10 puzzles preselected for the review of Brian Challenger’s Super Fiendish Sudoku, SF 67. , and then adds one of the bypass victims, SF 77. Looking at the trace, you might … Continue reading

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A Coloring Tidal Wave Drowns Sufi 37


Here, Brian Challenger’s Super Fiendish 37 makes it to advanced, but with the bi-value field   inviting multi-cluster coloring, a systematically easy solving technique. There are some X-panel fruits to harvest first in the order of battle, before coloring closes the … Continue reading

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