The New Sudoku Players' Forum

[champagne]

Setting up files for users of potential hardest puzzles I got a surprising result.
The solution grid 1339521744 has 49 puzzles rating skfr >=10.5
All these sudokus have 23 clues and a skfr EP >=10.5

For such puzzles, we have no expand reduction with my process, so we end with this list

Hidden Text: Show

Code: Select all

1...567......8..3.6..2.74.....64.5..5.............5.17..2......7....41...9.....7. ED=11.3/11.3/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......7....41...9.....7. ED=11.1/11.1/2.6
1....67......8..3.6..2.745....64.5..5.............5.17..2......7....41...9.....7. ED=11.0/11.0/2.6
1....67......8..3.6..2.745....64.5..5.............5.17..2.....57....41...9....... ED=11.0/11.0/2.6
1....67.9....8..3.6....745....64.5..5.............5.17..2......7....41...9.....7. ED=11.0/11.0/2.6
1....67.9....8..3.6....745....64.5..5.............5.17..2......7....41...9..6.... ED=11.0/11.0/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......7....41...9..6.... ED=11.0/11.0/2.6

1....67......8..3.6..2.745....64.5..5.............5.17..2......7....41...9..6.... ED=10.9/10.9/2.6
1....67......8..3.6..2.745....64.5..5.............5.17..2......7....41...91...... ED=10.9/10.9/2.6
1....67.9....8..3.6....745....64.5..5.............5.17..2......7....41...91...... ED=10.9/10.9/2.6
1....67.9....8..3.6....745....64.5..5.............5.17..2.....57....41...9....... ED=10.9/10.9/2.6
1....67.9..7.8..3.6....745..7.64.5..5.............5.17..2......7....41...9....... ED=10.9/10.9/2.6
1...567......8..3.6..2.74.....64.5..5.............5.17..2......7....41...9..6.... ED=10.9/10.9/2.6
1...567......8..3.6..2.74.....64.5..5.............5.17..2......7....41...9.5..... ED=10.9/10.9/2.6
1...567......8..3.6..2.74.....64.5..5.............5.17..2......7....41...91...... ED=10.9/10.9/2.6
1...567....7.8..3.6..2.74...7.64.5..5.............5.17..2......7....41...9....... ED=10.9/10.9/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......7....41...9.5..... ED=10.9/10.9/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......7....41...91...... ED=10.9/10.9/2.6
1...567.9..7.8..3.6....74...7.64.5..5.............5.17..2......7....41...9....... ED=10.9/10.6/2.6

1....67.9....8..3.6....745....64.5..5.............5.17..2......7.5..41...9....... ED=10.8/10.8/2.6
1....67.9....8..3.6....745....64.5..5.............5.17..2......76...41...9....... ED=10.8/10.8/2.6
1....67.9....8..3.6....745....64.5..5..........4..5.17..2......7....41...9....... ED=10.8/10.8/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......7.5..41...9....... ED=10.8/10.5/2.6
1....67......8..3.6....745....64.5..5.............5.17..2......7....412..9.....7. ED=10.5/10.5/2.6
1....67......8..3.6....745....64.5..5.............5.17..2......7...941...9.....7. ED=10.6/10.6/2.6
1....67......8..3.6....745....64.5..5.............5.17..2......7...941...9..6.... ED=10.7/10.7/2.6
1....67......8..3.6....745....64.5..5.............5.17..2......7...941...91...... ED=10.7/10.7/2.6
1....67......8..3.68.2.74.....64.5..5.............5.17..2......7....41...9.....7. ED=10.7/10.7/2.6
1....67......8..3.6..2.745....64.5..5.............5.17..2......7.5..41...9....... ED=10.6/10.6/2.6
1....67......8..3.6..2.745....64.5..5.............5.17..2......76...41...9....... ED=10.6/10.6/2.6
1...567......8..3.6....74.....64.5..5.............5.17..2......7...941...9.....7. ED=10.6/10.6/2.6
1...567......8..3.6....74.....64.5..5.............5.17..2......7...941...91...... ED=10.6/10.6/2.6
1...567......8..3.6..2.74.....64.5..5..........4..5.17..2......7....41...9....... ED=10.6/10.6/2.6
1...567.9....8..3.6....74.....64.5..5.............5.17..2......76...41...9....... ED=10.6/10.6/2.6
1....67......8..3.6....745....64.5..5.............5.17..2.....57....412..9....... ED=10.5/10.5/2.6
1....67......8..3.6..2.745....64.5..5..........4..5.17..2......7....41...9....... ED=10.5/10.5/2.6
1....67......8..3.68..374.....64.5..5.............5.17..2......7....41...9.....7. ED=10.5/10.5/2.6
1....678.....8..3.68...74.....64.5..5.............5.17..2......7....41...9.....7. ED=10.5/10.5/2.6
1....678.....8..3.68...74.....64.5..5.............5.17..2......7....41...9..6.... ED=10.5/10.5/2.6
1....678.....8..3.68...74.....64.5..5.............5.17..2......7....41...9.5..... ED=10.5/10.5/2.6
1....678.....8..3.68...74.....64.5..5.............5.17..2......7....41...91...... ED=10.5/10.5/2.6
1...567......8..3.6....74.....64.5..5.............5.17..2......7...941...9..6.... ED=10.5/10.5/2.6
1...567......8..3.6..2.74.....64.5..5.............5.17..2......7.5..41...9....... ED=10.5/10.5/2.6
1...567......8..3.6..2.74.....64.5..5.............5.17..2......76...41...9....... ED=10.5/10.5/2.6
1.3..67......8..3.6...374.....64.5..5.............5.17..2......7....41...9.....7. ED=10.5/10.5/2.6
1.3..67......8..3.6...374.....64.5..5.............5.17..2......7....41...9..6.... ED=10.5/10.5/2.6
1.3..67......8..3.6...374.....64.5..5.............5.17..2......7.5..41...9....... ED=10.5/10.5/2.6
1.3..67......8..3.6...374.....64.5..5.............5.17..2.....57....41...9....... ED=10.5/10.5/2.6
1.3..678.....8..3.6....74.....64.5..5.............5.17..2......7....41...9.....7. ED=10.5/10.5/2.6

I am very busy these days, but I think this is worth to be studied by experts.
What can explain all these high ratings.
I think that all of them have a JE 2389 base r4c45, with a poor effect, something else common to all of them must be

[champagne]

I had a look at one grid, I see a double JE, so a puzzle easy to solve