Mate in 72

[Jouni]

I am tired of too easy mates. Here one 72 mover:

[D]k1b5/1p1p4/pP1Pp3/K2pPp2/1P1p1P2/3P1P2/5P2/8 w - -

Chest solution in 1 seconds (automatically)

1. Ka4 {+M72/72 0} Kb8 {-M71/71 0} 2. Ka3 {+M71/71 0} Ka8 {-M70/70 0} 3.
Kb3 {+M70/70 0} Kb8 {-M69/69 0} 4. Kc2 {+M69/69 0} Ka8 {-M68/68 0} 5. Kd2
{+M68/68 0} Kb8 {-M67/67 0} 6. Ke2 {+M67/67 0} Ka8 {-M66/66 0} 7. Kf1
{+M66/66 0} Kb8 {-M65/65 0} 8. Kg2 {+M65/65 0} Ka8 {-M64/64 0} 9. Kg3
{+M64/64 0} Kb8 {-M63/63 0} 10. Kh4 {+M63/63 0} Ka8 {-M62/62 0} 11. Kg5
{+M62/62 0} Kb8 {-M61/61} 12. Kf6 {+M61/61 0} Ka8 {-M60/60 0} 13. Ke7
{+M60/60 0} Kb8 {-M59/59 0} 14. Kd8 {+M59/59 0} a5 {-M58/58 0} 15. bxa5
{+M58/58 0} Ka8 {-M57/57 0} 16. Ke7 {+M57/57 0} Kb8 {-M56/56 0} 17. Kf6
{+M56/56 0} Ka8 {-M55/55 0} 18. Kg5 {+M55/55 0} Kb8 {-M54/54 0} 19. Kh4
{+M54/54 0} Ka8 {-M53/53 0} 20. Kh3 {+M53/53 0} Kb8 {-M52/52 0} 21. Kg2
{+M52/52 0} Ka8 {-M51/51 0} 22. Kf1 {+M51/51 0} Kb8 {-M50/50 0} 23. Ke1
{+M50/50 0} Ka8 {-M49/49 0} 24. Kd1 {+M49/49} Kb8 {-M48/48 0} 25. Kc2
{+M48/48 0} Ka8 {-M47/47 0} 26. Kb3 {+M47/47 0} Kb8 {-M46/46 0} 27. Kb4
{+M46/46 0} Ka8 {-M45/45 0} 28. Kc5 {+M45/45 0} Kb8 {-M44/44 0} 29. Kxd4
{+M44/44 0} Ka8 {-M43/43 0} 30. Ke3 {+M43/43 0} Kb8 {-M42/42 0} 31. Ke2
{+M42/42 0} Ka8 {-M41/41 0} 32. Kf1 {+M41/41 0} Kb8 {-M40/40 0} 33. Kg2
{+M40/40 0} Ka8 {-M39/39 0} 34. Kg3 {+M39/39 0} Kb8 {-M38/38 0} 35. Kh4
{+M38/38 0} Ka8 {-M37/37 0} 36. Kg5 {+M37/37 0} Kb8 {-M36/36} 37. Kf6
{+M36/36 0} Ka8 {-M35/35 0} 38. Ke7 {+M35/35 0} Kb8 {-M34/34 0} 39. Kd8
{+M34/34 0} d4 {-M33/33 0} 40. Ke8 {+M33/33 0} Ka8 {-M32/32 0} 41. Ke7
{+M32/32 0} Kb8 {-M31/31 0} 42. Kf6 {+M31/31 0} Ka8 {-M30/30 0} 43. Kg5
{+M30/30 0} Kb8 {-M29/29 0} 44. Kh4 {+M29/29 0} Ka8 {-M28/28 0} 45. Kh3
{+M28/28 0} Kb8 {-M27/27 0} 46. Kg2 {+M27/27 0} Ka8 {-M26/26 0} 47. Kf1
{+M26/26 0} Kb8 {-M25/25 0} 48. Ke1 {+M25/25 0} Ka8 {-M24/24 0} 49. Kd1
{+M24/24} Kb8 {-M23/23 0} 50. Kc2 {+M23/23 0} Ka8 {-M22/22 0} 51. Kb3
{+M22/22 0} Kb8 {-M21/21 0} 52. Kc4 {+M21/21 0} Ka8 {-M20/20 0} 53. Kxd4
{+M20/20 0} Kb8 {-M19/19 0} 54. Ke3 {+M19/19 0} Ka8 {-M18/18 0} 55. d4
{+M18/18 0} Kb8 {-M17/17 0} 56. Ke2 {+M17/17 0} Ka8 {-M16/16 0} 57. Kf1
{+M16/16 0} Kb8 {-M15/15 0} 58. Kg2 {+M15/15 0} Ka8 {-M14/14 0} 59. Kg3
{+M14/14 0} Kb8 {-M13/13 0} 60. Kh4 {+M13/13 0} Ka8 {-M12/12 0} 61. Kg5
{+M12/12 0} Kb8 {-M11/11} 62. Kf6 {+M11/11 0} Ka8 {-M10/10 0} 63. Ke7
{+M10/10 0} Kb8 {-M9/9 0} 64. Kd8 {+M9/9 0} Ka8 {-M8/8 0} 65. a6 {+M8/8 0}
Kb8 {-M7/7 0} 66. a7+ {+M7/7 0} Ka8 {-M6/6 0} 67. d5 {+M6/6 0} exd5 {-M5/5
0} 68. e6 {+M5/5 0} dxe6 {-M4/4 0} 69. Kxc8 {+M4/4 0} d4 {-M3/3 0} 70. d7
{+M3/3 0} d3 {-M2/2 0} 71. d8=Q {+M2/2 0} d2 {-M1/1 0} 72. Kc7# {+M1/1 0}

Jouni

[Jim Walker]

Are you sure Chest did not just find the solution in it's database? Either that or you have the worlds fastest computer.

[peter]

Are you sure Chest did not just find the solution in it's database? Either that or you have the worlds fastest computer.

It's not a matter of database cause Chest doesn't find it at once with others than SearchMode Automatic or Auto Turbo XKP or XPK. These 3 settings only bring the mate immediately, Database Analysis doesn't. And of course Chest has to be told it's mate in 72 too.

k1b5/1p1p4/pP1Pp3/K2pPp2/1P1p1P2/3P1P2/5P2/8 w - - 0 1

Analysis by ChestUCI Ver.5.1:

1.Ka4
+- (#72) Tiefe: 72/72 00:00:01 613kN
1.Ka4 Kb8 2.Ka3 Ka8 3.Kb3 Kb8 4.Kc2 Ka8 5.Kd2 Kb8 6.Ke2 Ka8 7.Kf1 Kb8 8.Kg2 Ka8 9.Kg3 Kb8 10.Kh4 Ka8 11.Kg5 Kb8 12.Kf6 Ka8 13.Ke7 Kb8 14.Kd8 a5 15.bxa5 Ka8 16.Ke7 Kb8 17.Kf6 Ka8 18.Kg5 Kb8 19.Kh4 Ka8 20.Kh3 Kb8 21.Kg2 Ka8 22.Kf1 Kb8 23.Ke1 Ka8 24.Kd1 Kb8 25.Kc2 Ka8 26.Kb3 Kb8 27.Kb4 Ka8 28.Kc5 Kb8 29.Kxd4 Ka8 30.Ke3 Kb8 31.Ke2 Ka8 32.Kf1 Kb8 33.Kg2 Ka8 34.Kg3 Kb8 35.Kh4 Ka8 36.Kg5 Kb8 37.Kf6 Ka8 38.Ke7 Kb8 39.Kd8 d4 40.Ke8 Ka8 41.Ke7 Kb8 42.Kf6 Ka8 43.Kg5 Kb8 44.Kh4 Ka8 45.Kh3 Kb8 46.Kg2 Ka8 47.Kf1 Kb8 48.Ke1 Ka8 49.Kd1 Kb8 50.Kc2 Ka8 51.Kb3 Kb8 52.Kc4 Ka8 53.Kxd4 Kb8 54.Ke3 Ka8 55.d4 Kb8 56.Ke2 Ka8 57.Kf1 Kb8 58.Kg2 Ka8 59.Kg3 Kb8 60.Kh4 Ka8 61.Kg5 Kb8 62.Kf6 Ka8 63.Ke7 Kb8 64.Kd8 Ka8 65.a6 Kb8 66.a7+ Ka8 67.d5 exd5 68.e6 dxe6 69.Kxc8 d4 70.d7 d3 71.d8D d2 72.Kc7#
+- (#72) Tiefe: 72/72 00:00:01 734kN

My PC surely isn't the fastest and Chest uses one core only.

[David Dahlem]

Are you sure Chest did not just find the solution in it's database? Either that or you have the worlds fastest computer.

It's not a matter of database cause Chest doesn't find it at once with others than SearchMode Automatic or Auto Turbo XKP or XPK. These 3 settings only bring the mate immediately, Database Analysis doesn't. And of course Chest has to be told it's mate in 72 too.

I think it is a matter of database. I did a test, with the database and with the database removed. Try this test and you will see a big difference.