Classification-of-TE2-Sudokus

BpB classification of T&E(2) 9x9 Sudokus

The concepts and theories necessary to understand this repository — in particular braids[p], the T&E(n) procedure, the T&E-depth of a puzzle and the BpB classification of puzzles in T&E(2) — were first defined in [CRT] and then reproduced in all the editions of [PBCS].
[HCCS] includes a summary presentation of them.
General conclusions drawn from the detailed classifications below are available in [HCCS].

Contents of this repository

Currently, the main contents of this repository is a unique folder, eleven-26370.
More folders with similar results might be added later to this repository, when more T&E(2) puzzles are found.

The eleven-26370 folder includes:

the list [eleven 2011b] of 26,370 puzzles created by "eleven" according to the principles defined in [eleven 2011a]; they are pattern independent – the main reason why we chose this collection in [PBCS] and why we keep using it here and in [HCCS] as our reference for T&E(2) puzzles; the original link to the puzzles having been lost, they are reproduced here with eleven's agreement;
the sudo-eleven.pdf document ("Hardest Sudokus", May 27, 2011), a detailed presentation of the construction method and a complement to [eleven 2011a];
the BpB.txt file, containing the BpB classifications of all these puzzles — the main motivation for creating this repository; all computations were done with the [SHC] software;
the SER.txt file, containing the SER ratings of all these puzzles, mainly used in [HCCS] to compute the vague correlation between the SER and the BpB classification.

Results computed with [SudoRules] for a sublist of 1,278 puzzles were published as Table 11.2 and followig remarks in [PBCS]; they were used to check that the [SudoRules] and [SHC] results coincided.
The detailed results given here for the full list of puzzles were used in Table 2.2 of [HCCS], an extension of Table 11.2 of [PBCS].

References

Publications

[CRT]: BERTHIER D., Constraint Resolution Theories, Lulu Press, October 2011.
[eleven 2011a]: http://forum.enjoysudoku.com/the-making-of-a-gotchi-a-simple-way-to-find-extreme-sudokus-t30150.html
[HCCS]: BERTHIER D., Hierarchical Classifications in Constraint Satisfaction, Lulu Press, October 2023.
[PBCS1]: BERTHIER D., Pattern-Based Constraint Satisfaction and Logic Puzzles, Lulu Press, July 2012.
[PBCS2]: BERTHIER D., Pattern-Based Constraint Satisfaction and Logic Puzzles (Second Edition), Lulu Press, November 2015.
[PBCS3]: BERTHIER D., Pattern-Based Constraint Satisfaction and Logic Puzzles (Third Edition), Lulu Press, November 2021.
[PBCS]: any of [PBCS1], [PBCS2] or [PBCS3].

Software and puzzles

[eleven 2011b]: 26,370 T&E(2) puzzles, original broken link: https://sites.google.com/site/sudoeleven/ 08/07/2011
[SHC]: CORDOLIANI F., https://github.com/denis-berthier/Sudoku_Hierarchical_Classifier
[SudoRules]: BERTHIER D., part of: https://github.com/denis-berthier/CSP-Rules-V2.1