Quest for THE 16 GIVEN SUDOKU

coloin · Posted: Tue Apr 15, 2008 7:27 pm Post subject:

A little thought on what we are doing here.......

I dont think 221M {-0+5} is going to be possible !

However, possibly, an improved method, is to compare the common clues in the puzzles from the minlex grid solutions. I think I half-heartedly tried it a while back.

I was able to do a cumbersome and incomplete {-0+4} on a random selection of 1000 x 13 clue subpuzzles. The subpuzzles were from the puzzles in the minlex representation of the grid. I got the original 17s but not surprizingly not new ones. I enlisted the help of the fixed clues in the minlex grid solutions. I am sure it could be optimized.

Before we consider this on a big scale, we should ask how remote are recently found 17-puzzles are ?

If we take the puzzles which solve to the minlex grid, how many of the 12-subpuzzles from the new 17-puzzle correalate directly with any from the set of all 12 puzzles from the total 17-puzzles. I did a small scale version of this, comparing the 12s from a remote puzzle with 12s from 200 other 17 puzzles [all puzzles give minlex soutions] the maximum overlap of clues that I could find was 4 clues out of the 12.[disappointing] Grid solutions with more than one 17-puzzle would taint this complete analysis.

This shows that using fixed clues probably aint going to work.

The reason why every puzzle has a neighbour with 12 clues the same is due to the large number of isomorphic variations of each individual puzzle, and, of course, the large number of 17-puzzles.

C

gsf · Posted: Thu Apr 17, 2008 3:11 pm Post subject:

ChPicard has just recorded 2 new 17s
I'm currently at the random luck stage with my current strategy and it looks like luck is running out
did you apply some new strategy or old luck?

coloin · Posted: Fri May 09, 2008 7:00 pm Post subject: