The New Sudoku Players' Forum

[r.e.s.]

(grr, do you people also have the problem, that the
editing window is gone after opening another window
e.g. for searching for links ?)

Many browsers (e.g. IE) let you open a second window that duplicates the current page -- not sure if that's what you're doing. Doing that while the editing window is current should allow you to use the duplicate window to go searching, etc, leaving the original editing window untouched. (Similarly, it often pays to right-click to open a link in a new window.) Sorry if I've misunderstood, and you are already doing those things.

[Moschopulus]

this wasn't constructed, I just searched the t-invariant grids.

Why just search the t-invariant grids? Do they have a higher probability of having a high MCN?

I checked the file of t-invariant grids on your web page, the highest MCN is 16 (5 grids have this MCN). None have MCN = 17.

I checked the MCN = 16 grid for a 16 in about 15 minutes (using checker64). None exists of course. I checked it for a 17 in under 90 minutes, again none. I'll check it for an 18, should take about 6 hours.

[dukuso]

the idea for checking the t-invariants was,
that when there is a grid with many horizontal
unavoidables, then their transpose has the
same property vertically.

"all properties are squared" so to speak.

[Moschopulus]

I plotted the MCNs of the t-invariant grids against the ones I did previously here:
http://forum.enjoysudoku.com/viewtopic.php?t=605&start=315



Normalized to have 13919 grids in each sample.

blue=random grids, red=grids with 17, green=t-invariant grids