Tag Archives: hidden unique rectangle

Only Extreme 304 is AIC Level

This post and the next update Castillo’s Only Extreme Sudoku review with a solution of OnEx 304 without trials. Most of the solution path is in AIC building, the most challenging level of Sysudoku Advanced. The only move prior to … Continue reading

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

Beyond the Rectangle

The alternative deadly uniqueness formations of the Sudocue Guide are detailed in this post.  Also, there is a UR checkpoint on Sheldon’s Master Class # 3 that goes beyond the UR cases surveyed in recent posts. I can’t leave the … Continue reading

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

Stuart’s Hidden UR

In Logic of Sudoku, Andrew Stuart describes a unique rectangle with only one bv corner.  The tell-tale naked pair is not there.  Stuart calls this formation a hidden UR, with good reason.  You have to find the bv candidates in … Continue reading

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