Come back to scan mobydam

[TAILLE]

Yes Fabien I do not forget that it was a rapid game. For your information, even with a lot of time, Damy chooses 40-35 instead of 39-33!

Scan also likes 40-35 a lot, as it appears to give white a huge advantage. But black can draw; kudos to you for finding the line.

BTW is your centre evaluation depending of the number of pieces remaining on the board?

In Scan, the scoring of any evaluation feature can depend on the game phase. It is up to the learning algorithm to decide whether to use that option.

I have, however, no idea what the features are. Even if you could describe "centre evaluation" precisely, I would have trouble finding out what Scan thinks of it.

Hi Fabien,

Maybe I have found an interesting defense for black after 39-33:


black to play

3-9 49-43 9-13 33-28 14-20 28x37 20-25 40-35 23-29 34x29 25x34 draw!

[Fabien Letouzey]

Hi Fabien,

Maybe I have found an interesting defense for black after 39-33:


black to play

3-9 49-43 9-13 33-28 14-20 28x37 20-25 40-35 23-29 34x29 25x34 draw!

Huh? I have already given that line to you.

[TAILLE]

Hi Fabien,

Maybe I have found an interesting defense for black after 39-33:


black to play

3-9 49-43 9-13 33-28 14-20 28x37 20-25 40-35 23-29 34x29 25x34 draw!

Huh? I have already given that line to you.

Yes Fabien you already mentionned the possibililty 3-9 49-43 9-13 33-28 14-20 28x37 20-25 and here, by adding only 40-35 23-29 34x29 25x34, Damy is able to prove the draw (but not whithin 30" !!!)

[TAILLE]

Hi,

This game has not yet given all its secrets!


Black to play

We have seen that in this position black can reach the draw by 23-29.
In the game black played 15-20 and I said in a previous post that this move were probably a losing move but now I am not quite sure about that.
Let's take the game after (15-20) 49-43 (23-28) 34-29


Black to play

Instead of (12-17) played in the game I propose (20-25) on which Damy is unable to find a winning white move.

For your information on
(20-25) 30-24 Damy plays (4-10)
and on
(20-25) 39-34 Damy chooses (14-19)

Do you see (with the help of your program and a lot of time!) a winning line after (20-25) ?

[Sidiki]

Hi,

This game has not yet given all its secrets!


Black to play

We have seen that in this position black can reach the draw by 23-29.
In the game black played 15-20 and I said in a previous post that this move were probably a losing move but now I am not quite sure about that.
Let's take the game after (15-20) 49-43 (23-28) 34-29


Black to play

Instead of (12-17) played in the game I propose (20-25) on which Damy is unable to find a winning white move.

For your information on
(20-25) 30-24 Damy plays (4-10)
and on
(20-25) 39-34 Damy chooses (14-19)

Do you see (with the help of your program and a lot of time!) a winning line after (20-25) ?

Hi taille,

There is a lot of wins in this position after 20-25 the best move it's 39-34, even after 14-19 the position it's won excepted one variation that give draw. Just to say that it's a winning position.

I done some test of 15 min / 75 moves With Kingsrow 1.58 and Scan 2.0

Perspective for Kingsrow 8 wins , 8 losses, 3 draws, 1 unknow (that it's also draw)
I post here the pdn file and the content in text mode.

position Scan Moby.PDN

(15.04 KiB) Downloaded 500 times

[Event "Game 1, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 8-13 5. 34-29 25x23 6. 42-38 19x30 7. 38x29 30-34 8. 29x40 13-18 9.

43-38 3-9 10. 41-37 9-13 11. 40-34 4-10 12. 34-29 28-33 13. 29-24 33x42 14. 37x48 18-22 15. 24-20 13-18 16. 35-30 22-28 17.

30-24 28-33 18. 48-43 18-23 19. 20-15 10-14 20. 24-19 23-29 21. 19x10 29-34 22. 10-5 33-39 23. 31-26 39x48 24. 5-28 34-40

25. 28x6 48-37 26. 6-50 37-48 27. 15-10 40-45 28. 16-11 48-43 29. 11-7 43-32 30. 10-5 32-16 31. 7-2 16-27 32. 5-23 27-4 33.

2-35 4-15 34. 35-49 15-4 35. 26-21 4-15 36. 23-1 15-4 37. 21-17 4-15 38. 1-6 15-20 39. 50-33 20x38 40. 49x32 45-50 41. 32-

38 50x11 42. 6x17 *

[Event "Game 2, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 31-27 19-23 4. 27x38 12-17 5. 21x12 8x17 6. 42-37 17-21 7. 38-32 21-26 8. 41-36 3-8 9. 30-24

8-12 10. 24-19 23x14 11. 32x23 9-13 12. 43-38 14-20 13. 35-30 13-19 14. 23x14 20x9 15. 30-24 9-14 16. 38-32 12-17 17. 32-27

17-22 18. 37-32 22x31 19. 36x27 18-22 20. 27x18 26-31 21. 32-27 31x13 22. 29-23 25-30 23. 34x25 14-19 24. 23x14 13-18 25.

14-10 18-22 26. 10-5 22-27 27. 5-37 27-32 28. 37x28 *

[Event "Game 3, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 41-36 19-23 4. 31-27 12-17 5. 21x12 8x17 6. 27x38 17-21 7. 42-37 3-8 8. 43-39 21-26 9. 39-33

28x39 10. 34x43 25x34 11. 29x40 8-13 12. 40-34 18-22 13. 35-30 22-27 14. 30-24 13-18 15. 38-33 18-22 16. 33-29 23-28 17.

24-19 26-31 18. 37x26 27-32 19. 36-31 22-27 20. 31x33 32-37 21. 33-28 37-41 22. 43-38 41-47 23. 19-14 47x24 24. 14x3 24-13

25. 26-21 13-19 26. 28-22 19-23 27. 34-30 23-32 28. 21-16 32-43 29. 30-25 43-39 30. 3-17 39-34 31. 16-11 34-29 32. 11-6 29

-23 33. 25-20 23-7 34. 20-14 7-1 35. 14-9 1-7 36. 6-1 7-2 37. 9-4 2-24 38. 4-18 24-19 39. 17-6 19-2 40. 1-7 2x50 41. 18-22

50x17 42. 6x22 *

[Event "Game 4, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 31-27 9-14 4. 27x38 28-33 5. 29-23 18x40 6. 35x44 25x34 7. 38x40 8-13 8. 43-38 3-9 9. 21-16

12-17 10. 38-32 13-18 11. 32-27 19-23 12. 27-21 17x26 13. 16-11 18-22 14. 11-7 14-20 15. 7-1 23-28 16. 1-6 20-25 17. 40-35

9-13 18. 42-37 13-18 19. 44-39 28-32 20. 37x17 26-31 21. 39-33 18-23 22. 6-1 23-29 23. 1x45 25-30 24. 35x24 31-36 25. 41-37

36-41 26. 37x46 *

[Event "Game 5, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 41-36 19-23 4. 31-27 12-17 5. 21x12 8x17 6. 27x38 17-21 7. 42-37 3-8 8. 43-39 21-26 9. 39-33

28x39 10. 34x43 25x34 11. 29x40 9-14 12. 38-33 18-22 13. 37-32 22-27 14. 32x21 26x17 15. 43-38 14-20 16. 38-32 20-24 17.

33-28 23-29 18. 32-27 8-13 19. 36-31 13-19 20. 31-26 19-23 21. 28x30 29-33 22. 27-21 17-22 23. 21-16 22-27 24. 16-11 27-32

25. 11-7 33-38 26. 7-2 32-37 27. 2-19 37-42 28. 19-37 42x31 29. 26x37 38-43 30. 40-34 43-48 31. 37-32 48-31 32. 30-25 31-18

33. 34-30 18-23 34. 32-27 23-18 35. 27-21 18-12 36. 21-16 12-1 37. 25-20 1-6 38. 30-24 6-50 39. 20-15 50-28 40. 24-20 28-6

41. 15-10 6-28 42. 10-5 28-33 43. 20-15 33-22 44. 5-46 22-17 45. 15-10 17-33 46. 35-30 33-15 47. 10-4 15-20 48. 16-11 20-33

49. 11-7 33-29 50. 7-2 29-40 51. 30-24 40-34 52. 2-19 34-45 53. 4-15 45-50 54. 19-28 50x22 55. 46-28 22x20 56. 15x24 *

[Event "Game 6, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 8-13 3. 31-27 3-9 4. 27x38 28-33 5. 29-23 18x40 6. 35x44 25x34 7. 38x40 13-18 8. 42-38 9-14 9. 41-

37 4-9 10. 21-16 12-17 11. 38-32 19-23 12. 43-38 14-19 13. 44-39 19-24 14. 38-33 18-22 15. 40-34 23-28 16. 32x23 9-14 17.

34-29 14-20 18. 39-34 22-27 19. 16-11 17x6 20. 23-18 6-11 21. 18-12 11-16 22. 12-7 16-21 23. 7-1 21-26 24. 1-18 26-31 25.

37x26 27-32 26. 18-23 32-38 27. 33x42 24x33 28. 23-12 33-39 29. 34x43 20-25 30. 12-8 25-30 31. 8x35 *

[Event "Game 7, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 19-23 5. 42-38 32-37 6. 31x42 8-12 7. 34-29 23x34 8. 30x39 12-18 9.

24-19 3-8 10. 38-33 18-23 11. 43-38 23x14 12. 42-37 8-13 13. 37-31 25-30 14. 35x24 13-19 15. 24x13 4-9 16. 13x4 14-19 17.

4x27 17-21 18. 33x22 21x34 19. 16-11 34-39 20. 11-7 39-43 21. 7-1 43-48 22. 31-26 48-25 23. 22-17 25-14 24. 41-36 19-24 25.

17-11 14-28 26. 11-7 28-44 27. 1-6 44-40 28. 7-1 40-49 29. 1-7 24-30 30. 6-22 49-32 31. 7-2 32-16 32. 2x35 16-43 33. 36-31

43-48 34. 31-27 48-34 35. 26-21 34-23 36. 35-44 23-37 37. 21-16 37-26 38. 22-13 26-3 39. 44-17 3x32 40. 13-27 32x21 41.

16x27 *

[Event "Game 8, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "1-1"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 31-27 9-13 4. 27x38 28-33 5. 41-37 33x24 6. 37-32 3-9 7. 38-33 18-22 8. 32-28 22-27 9. 21x32

13-18 10. 43-38 12-17 11. 32-27 19-23 12. 28x19 24x13 13. 42-37 13-19 14. 37-31 8-12 15. 33-28 9-14 16. 38-33 14-20 17. 33

-29 19-23 18. 28x19 20-24 19. 29x20 25x23 20. 30-24 17-22 21. 31-26 22x31 22. 26x37 23-28 23. 24-19 28-33 24. 19-14 33-38

25. 37-32 38x27 26. 14-10 27-32 27. 10-4 18-23 28. 4-10 23-28 29. 34-29 12-18 30. 35-30 18-23 31. 29x18 28-33 *

[Event "Game 9, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 19-23 5. 42-38 32-37 6. 31x42 8-12 7. 34-29 23x34 8. 30x39 12-18 9.

41-36 3-9 10. 38-33 9-13 11. 43-38 4-9 12. 36-31 13-19 13. 24x4 18-23 14. 4x27 17-21 15. 33x22 21x34 16. 16-11 34-39 17.

11-7 39-44 18. 7-1 44-50 19. 1x34 50x17 20. 31-27 17-11 21. 27-21 11-33 22. 42-37 33-28 23. 37-31 28-22 24. 31-26 22-33 25.

21-16 33-17 26. 34-48 17-6 27. 26-21 6-50 28. 48-34 50-45 29. 34-1 45-50 30. 1-45 50-6 31. 45-50 6-1 32. 21-17 1-18 33. 50

-45 18-13 34. 17-12 13-4 35. 45-34 4-9 36. 35-30 9-36 37. 12-8 36-4 38. 16-11 4-15 39. 11-7 15-4 40. 7-1 4-36 41. 1-6 36-47

42. 8-3 47-36 43. 3-17 36-47 44. 30-24 47x15 45. 34-29 15x11 46. 6x39 25-30 47. 39x25 *

[Event "Game 10, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 4-10 2. 26-21 14-19 3. 41-36 19-23 4. 21-16 32-37 5. 42-38 37x26 6. 16-11 10-15 7. 11-6 12-17 8. 6-1 17-22 9. 1-7

26-31 10. 36x27 22x31 11. 30-24 8-12 12. 7-11 31-37 13. 11x50 37-41 14. 50-45 15-20 15. 24x15 41-46 16. 45-50 12-17 17.

50x6 23-28 18. 6x50 46-5 19. 38-33 5-37 20. 43-38 25-30 21. 34x25 18-22 22. 29-24 37-31 23. 38-32 31-48 24. 15-10 48-34 25.

50-45 34-43 26. 45-50 43x16 27. 33-28 22x33 28. 50x11 16x30 29. 35x24 3-9 30. 24-19 9-14 31. 10-5 14x23 32. 5x28 *

[Event "Game 11, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "1-1"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 8-13 5. 34-29 25x23 6. 42-38 19x30 7. 38x29 30-34 8. 29x40 3-8 9. 41

-37 13-19 10. 35-30 8-12 11. 40-34 28-33 12. 43-38 33x42 13. 37x48 4-10 14. 34-29 10-15 15. 29-24 19-23 16. 30-25 12-18 17.

48-43 18-22 18. 43-39 23-28 19. 39-34 28-32 20. 24-19 32-38 21. 19-13 38-42 22. 13-9 22-28 23. 31-26 *

[Event "Game 12, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 41-36 19-23 4. 21-16 32-37 5. 16-11 37x39 6. 34x43 25x34 7. 29x40 28-32 8. 11-6 12-17 9. 6-1

8-12 10. 31-26 32-37 11. 1-6 37-42 12. 6x4 42-47 13. 4-10 47-29 14. 10x28 29x45 15. 26-21 45-50 16. 28-6 50-45 17. 6-28 45

-29 18. 28-39 29-45 19. 39-50 45-23 20. 21-16 23-19 21. 50-45 12-17 22. 45-50 17-21 23. 16x27 19-8 24. 43-39 8-2 25. 27-21

2-16 26. 21-17 16-2 27. 50-45 2-8 28. 17-11 8-2 29. 11-6 2-8 30. 45-18 8-2 31. 39-34 3-8 32. 34-30 2-16 33. 30-24 16-38 34.

18-29 38-21 35. 6-1 21-16 36. 1-18 16-11 37. 29-23 11-17 38. 18-22 17x30 39. 35x24 8-13 40. 36-31 13-18 41. 31-27 18-23 42.

27-22 23-29 43. 24x33 *

[Event "Game 13, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 8-13 5. 34-29 25x23 6. 42-38 19x30 7. 38x29 30-34 8. 29x40 13-18 9.

41-37 4-9 10. 35-30 18-22 11. 30-24 28-33 12. 40-35 22-28 13. 35-30 9-14 14. 30-25 3-9 15. 24-20 14-19 16. 31-26 19-23 17.

20-14 9x20 18. 25x14 23-29 19. 14-9 29-34 20. 9-4 34-40 21. 4-31 40-44 22. 37-32 28x37 23. 31x24 44-50 24. 24-8 17-21 25.

16x27 50-44 26. 8-35 44-17 27. 27-21 17-33 28. 21-16 33-17 29. 43-38 17-22 30. 35-19 22-44 31. 19-23 44-35 32. 16-11 35-44

33. 11-6 44-49 34. 38-33 49-44 35. 23-28 44-40 36. 26-21 40-35 37. 6-1 35-24 38. 1-29 24-2 39. 21-16 2-8 40. 16-11 8-3 41.

11-7 3-8 42. 28-6 8-3 43. 7-1 3-8 44. 29-24 8x30 45. 1-34 30x28 46. 6x33 *

[Event "Game 14, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 31-27 8-13 4. 27x38 28-33 5. 29-23 18x40 6. 35x44 25x34 7. 38x40 19-23 8. 44-39 13-18 9. 41

-37 9-14 10. 39-33 3-8 11. 37-32 8-13 12. 32-27 12-17 13. 21x12 18x7 14. 40-34 7-12 15. 43-39 14-20 16. 27-22 23-28 17. 22

-17 12x21 18. 33x22 13-19 19. 22-18 20-25 20. 18-12 19-24 21. 12-8 24-30 22. 8-2 30-35 23. 2-24 21-27 24. 42-37 27-32 25.

37x28 25-30 26. 34x25 35-40 27. 39-34 40x20 28. 25x14 *

[Event "Game 15, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 19-23 5. 42-38 32-37 6. 31x42 8-12 7. 34-29 23x34 8. 30x39 12-18 9.

24-19 4-9 10. 38-33 18-23 11. 42-37 23x14 12. 43-38 9-13 13. 37-31 25-30 14. 35x24 13-19 15. 24x13 3-9 16. 13x4 14-19 17.

4x27 17-21 18. 33x22 21x34 19. 16-11 34-39 20. 11-7 39-43 21. 7-1 43-48 22. 31-26 48-25 23. 22-17 25-9 24. 41-36 9-27 25.

17-11 27-16 26. 11-6 16-49 27. 1-34 19-24 28. 6-1 49-16 29. 1-18 16-2 30. 18-4 2-7 31. 34x1 24-29 32. 1x34 *

[Event "Game 16, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 19-23 3. 42-38 32-37 4. 31x42 12-17 5. 21x12 8x17 6. 42-37 3-8 7. 38-32 4-9 8. 32-27 17-22 9. 27-21

9-13 10. 41-36 13-19 11. 43-39 19-24 12. 30x19 23x14 13. 29-24 8-12 14. 24-20 14-19 15. 20-15 18-23 16. 15-10 19-24 17. 10

-5 12-18 18. 37-32 28x37 19. 5x46 25-30 20. 34x25 24-29 21. 36-31 18-23 22. 46x5 22-28 23. 5x32 29-34 24. 39x30 *

[Event "Game 17, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "*"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 41-36 19-23 4. 31-27 12-17 5. 21x12 8x17 6. 27x38 3-8 7. 42-37 8-12 8. 36-31 17-21 9. 38-32

21-26 10. 31-27 12-17 11. 43-38 17-21 12. 27x16 26-31 13. 37x26 28x37 14. 16-11 37-41 15. 11-7 41-46 16. 26-21 23-28 17.

29-24 9-13 18. 21-16 46-41 19. 38-33 28x39 20. 34x43 25x34 21. 24-20 18-22 22. 20-15 13-18 23. 16-11 22-27 24. 7-2 41-23

25. 2-24 27-31 26. 11-6 23-5 27. 6-1 34-39 28. 43x34 31-36 29. 1x29 36-41 30. 35-30 41-46 31. 30-25 46-28 32. 34-30 28-22

33. 29-12 22-27 34. 12-29 27-16 35. 29-12 16-27 36. 12-29 27-16 37. 24-13 5-46 38. 29-24 46-28 39. 13-18 28-5 40. 24-2 16-

49 41. 30-24 5-46 42. 2-8 49-44 43. 8-2 46-41 44. 2-8 41-46 45. 8-2 44-49 46. 18-34 49-32 47. 2-8 46-37 48. 8-13 32-21 49.

13-18 37-46 50. 34-30 21-49 51. 30-35 49-32 52. 18-29 32-5 53. 29-34 5-28 54. 34-40 28-5 55. 35-30 5-37 56. 30-35 37-5 57.

35-30 5-14 58. 40-1 14-28 59. 1-7 28-5 60. 7-12 46-28 61. 12-18 28-41 62. 18-29 41-46 63. 29-34 5-32 64. 30-35 32-28 65.

34-45 28-41 66. 35-40 41-14 67. 40-44 14-5 68. 44-49 5-14 69. 45-50 14-5 70. 49-44 5-23 71. 44-49 23-1 72. 49-44 1-45 73.

44-49 45-1 74. 49-44 1-23 75. 44-35 23-32 76. 35-40 32-5 77. 40-49 5-14 78. 49-40 14-5 79. 40-49 5-14 80. 50-22 14-5 81.

49-35 5-23 82. 22-33 23-5 83. 33-39 5-23 84. 35-44 23-45 85. 39-43 *

[Event "Game 18, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "1-1"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-10 3. 41-36 19-23 4. 31-27 12-17 5. 21x12 8x17 6. 27x38 3-8 7. 36-31 17-22 8. 42-37 8-12 9. 43-39

12-17 10. 38-32 17-21 11. 31-26 10-14 12. 26x17 22x11 13. 30-24 25-30 14. 34x25 23x43 15. 32x12 43-48 16. 37-31 48x30 17.

35x24 11-17 18. 24-20 14-19 19. 20-15 19-24 20. 25-20 24-30 *

[Event "Game 19, opening start position 1"]
[Date "2017.07.06"]
[White "Kingsrow 1.58"]
[Black "Scan 2.0"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 18-22 3. 21-16 12-17 4. 29-24 19-23 5. 42-38 32-37 6. 31x42 8-12 7. 34-29 23x34 8. 30x39 12-18 9.

41-36 3-9 10. 38-33 9-13 11. 43-38 4-9 12. 36-31 13-19 13. 24x4 18-23 14. 4x27 17-21 15. 33x22 21x34 16. 16-11 34-39 17.

11-7 39-44 18. 7-1 44-50 19. 1x45 50x6 20. 42-38 6-22 21. 31-26 22-13 22. 45-34 13-24 23. 38-32 24-19 24. 32-27 19-13 25.

27-21 13-22 26. 34-29 22-6 27. 29-45 6-50 28. 21-16 50-6 29. 45-50 6-1 30. 16-11 1-29 31. 11-6 29-15 32. 50-39 15-38 33. 6

-1 25-30 34. 39x25 38-33 35. 1-6 33-15 36. 26-21 15-10 37. 21-17 10-37 38. 17-12 37-41 39. 12-8 41-5 40. 8-2 5-23 41. 2-24

23-45 42. 24-33 45-23 43. 25-34 23x45 44. 6-1 45-50 45. 1-6 50x28 46. 6x33 *

[Event "Game 20, opening start position 1"]
[Date "2017.07.06"]
[White "Scan 2.0"]
[Black "Kingsrow 1.58"]
[Result "2-0"]
[FEN "W:W26,29,30,31,35,39,41,42,43:B3,4,8,12,14,18,25,28,32"]
1. 39-34 14-19 2. 26-21 4-9 3. 31-27 9-13 4. 27x38 28-33 5. 41-37 33x24 6. 37-32 3-9 7. 38-33 18-22 8. 32-28 22-27 9. 21x32

13-18 10. 42-37 12-17 11. 32-27 18-23 12. 37-32 9-13 13. 27-22 17-21 14. 34-29 23x34 15. 30x39 24-30 16. 35x24 19x30 17.

22-18 13x22 18. 28x26 8-13 19. 26-21 30-35 20. 43-38 13-19 21. 21-17 25-30 22. 32-28 19-23 23. 28x19 35-40 24. 17-11 30-34

25. 39x30 40-44 26. 38-32 44-50 27. 32-28 50-45 28. 19-14 45-40 29. 30-25 40-44 30. 14-10 44-49 31. 11-6 49-43 32. 10-4 43

-49 33. 4-18 49-35 34. 6-1 35-8 35. 1-6 8-2 36. 18-45 2-35 37. 33-29 35-49 38. 28-22 49-32 39. 29-23 32x19 40. 45-23 19x17

41. 6x22 *

[Fabien Letouzey]

Do you see (with the help of your program and a lot of time!) a winning line after (20-25) ?

The key position seems to be after (20-25) 39-34 14-19 26-21. Black has a lot of options but is in big trouble (score around -2). What is your move?

[TAILLE]

Do you see (with the help of your program and a lot of time!) a winning line after (20-25) ?

The key position seems to be after (20-25) 39-34 14-19 26-21. Black has a lot of options but is in big trouble (score around -2). What is your move?

Hi Fabien,

Yes black is in trouble and it is a great challenge for Damy and other programs to try and find a draw.

(20-25) 39-34 (14-19) 26-21


Black to move

Now Damy plays (4-10)

Having seen all the games showed by Sidiki (thank you for this great work!) Damy continues like the game 10 with the following PV:

(4-10) 41-36 (19-23) 21-16 (32-37) 42-38 (37x26) 16-11 (8-13) 11-6 (13-19) and here I am pretty sure you will conclude to a draw

[Fabien Letouzey]

Now Damy plays (4-10)

Having seen all the games showed by Sidiki (thank you for this great work!) Damy continues like the game 10 with the following PV:

(4-10) 41-36 (19-23) 21-16 (32-37) 42-38 (37x26) 16-11 (8-13) 11-6 (13-19) and here I am pretty sure you will conclude to a draw

After (4-10) 41-36 19-23, Scan wants to play 42-38 12-17 21x12 18x7 38x27 8-12 29x18 12x23 (instead of 21-16).

However I feel that I can't trust scores from Scan 3 here, as it uses Killer-draughts evaluation even in normal-draughts games. One big difference is the scoring of additional kings: Scan 3 treats them as real kings (which is their power in Killer draughts), while Scan 2 sees them as mere men.

As a consequence if you see a clear draw after this line, which seems likely, I would accept it as a proof.

[TAILLE]

Now Damy plays (4-10)

Having seen all the games showed by Sidiki (thank you for this great work!) Damy continues like the game 10 with the following PV:

(4-10) 41-36 (19-23) 21-16 (32-37) 42-38 (37x26) 16-11 (8-13) 11-6 (13-19) and here I am pretty sure you will conclude to a draw

After (4-10) 41-36 19-23, Scan wants to play 42-38 12-17 21x12 18x7 38x27 8-12 29x18 12x23 (instead of 21-16).

However I feel that I can't trust scores from Scan 3 here, as it uses Killer-draughts evaluation even in normal-draughts games. One big difference is the scoring of additional kings: Scan 3 treats them as real kings (which is their power in Killer draughts), while Scan 2 sees them as mere men.

As a consequence if you see a clear draw after this line, which seems likely, I would accept it as a proof.

Yes Fabien the line (4-10) 41-36 (19-23) 42-38 (12-17) 21x12 (18x7) 38x27 (8-12) 29x18 (12x23) is a clear draw for Damy