A Pattern Analysis Attack on Nakex 103


This post reports an alternative Sysudoku solution to Nakamoto Extreme 103, starting with a pattern analysis signaled on an X-panel. The analysis develops and exploits a coloring cluster to accelerate the solution.

 

 

 

 

The starting cluster is expanded when West to East freeforms reveal that any pattern including 4r1c1 also includes 4r3c7. In other words, if blue 4r5c1 is false, then 4r3c7 is true, defining a slink carrying the colors across the grid to trap 4r1c3.

 

 

 

After this expansion, West to East freeforms for blue confine it to a single pattern, and the cluster wraps green, as two green 4’s are forced into c3, with follow up:

 

 

Now  AIC building is unnecessary. First  comes an XY-chain removing 6r6c4.

Then another for 7r4c5:

 

After a third ANL triggers a SEr9 boxline,

 

 

 

 

a large second cluster can be  added, just in time for a shortcut confirming ANL.

 

 

 

 

 

 

 

 

This sets up the identical confirming ANL from the Sudokuwiki path, but this time, for the collapse, as orange 9r5c5 wraps red.

 

 

 

The collapse trace and color version of the solution are below.

 

 

About Sudent

My real name is John Welch. I'm a happily married, retired professor, father of 3 wonderful daughters and granddad to 7 fabulous grandchildren. Sudoku analysis and illustration is a great hobby and a healthy mental challenge.
This entry was posted in Advanced Solving, Nakamoto, Puzzle Reviews and tagged , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s