To finally prove this famous mate-in-226 composition has a shorter solution, we must simplify the work. Anyhow I've found a way to reduce the computation. Now we just need to find the direct DTM of these 17 positions.Hobacle wrote: ↑Sun Feb 06, 2022 7:14 am The full pgn file of the #226:
[pgn][Event ""]
[Site ""]
[Date "2022.02.06"]
[Round ""]
[White ""]
[Black ""]
[Result "1-0"]
[FEN "1N2Q3/p6n/p5n1/p1p2rpb/p4k1r/K1P4p/2PP4/6B1 w - - 0 1"]
[SetUp "1"]
1. Bh2+ Kf3 2. Qe3+ Kg2 3. Qg1+ Kf3 4. Qf1+ Kg4 5. Qe2+ Rf3 6. Qe6+ Rf5 7. Nd7
Kf3 8. Qe3+ Kg2 9. Qg1+ Kf3 10. Qf1+ Kg4 11. Qe2+ Rf3 12. Qe6+ Rf5 13. Kb2 Kf3
14. Qe3+ Kg2 15. Qg1+ Kf3 16. Qf1+ Kg4 17. Qe2+ Rf3 18. Qe6+ Rf5 19. Kc1 Kf3
20. Qe3+ Kg2 21. Qg1+ Kf3 22. Qf1+ Kg4 23. Qe2+ Rf3 24. Qe6+ Rf5 25. Kd1 a3 26.
Kc1 Kf3 27. Qe3+ Kg2 28. Qg1+ Kf3 29. Qf1+ Kg4 30. Qe2+ Rf3 31. Qe6+ Rf5 32.
Kb1 Kf3 33. Qe3+ Kg2 34. Qg1+ Kf3 35. Qf1+ Kg4 36. Qe2+ Rf3 37. Qe6+ Rf5 38.
Ka2 Kf3 39. Qe3+ Kg2 40. Qg1+ Kf3 41. Qf1+ Kg4 42. Qe2+ Rf3 43. Qe6+ Rf5 44.
Kxa3 Kf3 45. Qe3+ Kg2 46. Qg1+ Kf3 47. Qf1+ Kg4 48. Qe2+ Rf3 49. Qe6+ Rf5 50.
Kb2 Kf3 51. Qe3+ Kg2 52. Qg1+ Kf3 53. Qf1+ Kg4 54. Qe2+ Rf3 55. Qe6+ Rf5 56.
Kc1 Kf3 57. Qe3+ Kg2 58. Qg1+ Kf3 59. Qf1+ Kg4 60. Qe2+ Rf3 61. Qe6+ Rf5 62.
Kd1 a4 63. Kc1 Kf3 64. Qe3+ Kg2 65. Qg1+ Kf3 66. Qf1+ Kg4 67. Qe2+ Rf3 68. Qe6+
Rf5 69. Kd1 a5 70. Kc1 Kf3 71. Qe3+ Kg2 72. Qg1+ Kf3 73. Qf1+ Kg4 74. Qe2+ Rf3
75. Qe6+ Rf5 76. Kd1 a6 77. Kc1 Kf3 78. Qe3+ Kg2 79. Qg1+ Kf3 80. Qf1+ Kg4 81.
Qe2+ Rf3 82. Qe6+ Rf5 83. Kd1 a3 84. Kc1 Kf3 85. Qe3+ Kg2 86. Qg1+ Kf3 87. Qf1+
Kg4 88. Qe2+ Rf3 89. Qe6+ Rf5 90. Kb1 Kf3 91. Qe3+ Kg2 92. Qg1+ Kf3 93. Qf1+
Kg4 94. Qe2+ Rf3 95. Qe6+ Rf5 96. Ka2 Kf3 97. Qe3+ Kg2 98. Qg1+ Kf3 99. Qf1+
Kg4 100. Qe2+ Rf3 101. Qe6+ Rf5 102. Kxa3 Kf3 103. Qe3+ Kg2 104. Qg1+ Kf3 105.
Qf1+ Kg4 106. Qe2+ Rf3 107. Qe6+ Rf5 108. Kb2 Kf3 109. Qe3+ Kg2 110. Qg1+ Kf3
111. Qf1+ Kg4 112. Qe2+ Rf3 113. Qe6+ Rf5 114. Kc1 Kf3 115. Qe3+ Kg2 116. Qg1+
Kf3 117. Qf1+ Kg4 118. Qe2+ Rf3 119. Qe6+ Rf5 120. Kd1 a4 121. Kc1 Kf3 122.
Qe3+ Kg2 123. Qg1+ Kf3 124. Qf1+ Kg4 125. Qe2+ Rf3 126. Qe6+ Rf5 127. Kd1 a5
128. Kc1 Kf3 129. Qe3+ Kg4 130. Qg1+ Kf3 131. Qf1+ Kg4 132. Qe2+ Rf3 133. Qe6+
Rf5 134. Kd1 a3 135. Kc1 Kf3 136. Qe3+ Kg2 137. Qg1+ Kf3 138. Qf1+ Kg4 139.
Qe2+ Rf3 140. Qe6+ Rf5 141. Kb1 Kf3 142. Qe3+ Kg2 143. Qg1+ Kf3 144. Qf1+ Kg4
145. Qe2+ Rf3 146. Qe6+ Rf5 147. Ka2 Kf3 148. Qe3+ Kg2 149. Qg1+ Kf3 150. Qf1+
Kg4 151. Qe2+ Rf3 152. Qe6+ Rf5 153. Kxa3 Kf3 154. Qe3+ Kg2 155. Qg1+ Kf3 156.
Qf1+ Kg4 157. Qe2+ Rf3 158. Qe6+ Rf5 159. Kb2 Kf3 160. Qe3+ Kg2 161. Qg1+ Kf3
162. Qf1+ Kg4 163. Qe2+ Rf3 164. Qe6+ Rf5 165. Kc1 Kf3 166. Qe3+ Kg2 167. Qg1+
Kf3 168. Qf1+ Kg4 169. Qe2+ Rf3 170. Qe6+ Rf5 171. Kd1 a4 172. Kc1 Kf3 173.
Qe3+ Kg2 174. Qg1+ Kf3 175. Qf1+ Kg4 176. Qe2+ Rf3 177. Qe6+ Rf5 178. Kd1 c4
179. Kc1 Kf3 180. Qe3+ Kg2 181. Qg1+ Kf3 182. Qf1+ Kg4 183. Qe2+ Rf3 184. Qe6+
Rf5 185. Kd1 a3 186. Kc1 Kf3 187. Qe3+ Kg2 188. Qg1+ Kf3 189. Qf1+ Kg4 190.
Qe2+ Rf3 191. Qe6+ Rf5 192. Kb1 Kf3 193. Qe3+ Kg2 194. Qg1+ Kf3 195. Qf1+ Kg4
196. Qe2+ Rf3 197. Qe6+ Rf5 198. Ka2 Kf3 199. Qe3+ Kg2 200. Qg1+ Kf3 201. Qf1+
Kg4 202. Qe2+ Rf3 203. Qe6+ Rf5 204. Kxa3 Kf3 205. Qe3+ Kg2 206. Qg1+ Kf3 207.
Qf1+ Kg4 208. Qe2+ Rf3 209. Qe6+ Rf5 210. Kb2 Kf3 211. Qe3+ Kg2 212. Qg1+ Kf3
213. Qf1+ Ke4 214. Qxc4+ Kf3 215. Qf1+ Kg4 216. Qe2+ Rf3 217. Qe6+ Rf5 218. Kc1
Kf3 219. Qe3+ Kg2 220. Qg1+ Kf3 221. Qf1+ Kg4 222. Qe2+ Rf3 223. Qe6+ Rf5 224.
Kd1 Nhf8 225. Nf6+ Kf3 226. Qe2# 1-0
[/pgn]
Code: Select all
1. 8/3N3n/K3Q1n1/2p2rpb/2PP2kr/2P4p/7B/8 b - - 0 1
The following positions are similar.
2. 8/K2N3n/6n1/2p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
3. 8/3N3n/K5n1/2p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
4. 8/p2N3n/K5n1/2p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
5. 8/3N3n/p5n1/K1p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
6. 8/p2N3n/6n1/K1p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
7. 8/p2N3n/p5n1/K1p2rpb/2P1k2r/2P4p/3P3B/5Q2 w - - 0 1
8. 8/3N3n/p5n1/p1p2rpb/K1P1k2r/2P4p/3P3B/5Q2 w - - 0 1
9. 8/p2N3n/6n1/p1p2rpb/K1P1k2r/2P4p/3P3B/5Q2 w - - 0 1
10. 8/p2N3n/p5n1/2p2rpb/K1P1k2r/2P4p/3P3B/5Q2 w - - 0 1
11. 8/p2N3n/p5n1/p1p2rpb/K1P1k2r/2P4p/3P3B/5Q2 w - - 0 1
12. 8/p2N3n/6n1/p1p2rpb/p1P1k2r/K1P4p/3P3B/5Q2 w - - 0 1
13. 8/p2N3n/p5n1/2p2rpb/p1P1k2r/K1P4p/3P3B/5Q2 w - - 0 1
14. 8/p2N3n/p5n1/p1p2rpb/2P1k2r/K1P4p/3P3B/5Q2 w - - 0 1
15. 8/p2N3n/p5n1/2p2rpb/p1P1k2r/p1P4p/K2P3B/5Q2 w - - 0 1
16. 8/p2N3n/p5n1/p1p2rpb/2P1k2r/p1P4p/K2P3B/5Q2 w - - 0 1
17. 8/p2N3n/p5n1/p1p2rpb/p1P1k2r/2P4p/1K1P3B/5Q2 w - - 0 1Thank you for any help you can offer.