Author: Uri Blass
Date: 09:01:48 09/26/00
Go up one level in this thread
On September 26, 2000 at 11:36:13, Steffen Jakob wrote: >On September 26, 2000 at 11:30:05, Jason Williamson wrote: > >>On September 26, 2000 at 11:25:03, Steffen Jakob wrote: >> >>>Hi all! >>> >>>I ran the GMG3 endgame test suite with Hossa. Here is the position #13: >>> >>>[D]5q2/6pk/p7/1p3PPK/1P2Q3/8/8/8 w >>> >>>The key move is 1.g6. >>> >>>After a while Hossa gave 1.f6 with a score of +10.47. I thought that maybe f6 is >>>a possible solution too. So I examined the PV of Hossa. It started with >>> >>>1.f6 h7g8 2.e4e6 f8f7 3.e6xf7 g8xf7 4.f6xg7 f7xg7 5.g6 >>> >>>which leads to this position: >>> >>>[D]8/6k1/p5P1/1p5K/1P6/8/8/8 b >>> >>>Here Hossa continued with 5... Kf6 which is indeed losing. All moves seem to be >>>losing here. But when I forced 5... b5 6. bxa5 Hossa gave a score of mate in 54! >>> >>>How is this such a position handled in tournament chess? Is this a draw (I think >>>the rules have changed here several times?!)? If it's a draw then I will change >>>my tablebase probe code to return a draw score if the mate distance is > 50. >>> >>>Best wishes, >>>Steffen. >> >>Don't forget that that mate in 54, the pawn will move several times, each time >>restarting the draw in 50 move rule count. > >Oooops :-) > >So can someone please confirm if 1.f6 is another solution? > >Greetings, >Steffen. There is no doubt that 1.f6 is a solution. White can get the following position that is mate in 50 [D]Q7/6k1/6P1/7K/8/8/8/1q6 w - - 0 1 The last move of black was b1Q so the counting of the 100 plies for the 50 move rule begins with this move so even if I assume no captures and no pawns moves it is a win by the chess rules. I am surprised to see that the position is mate in 50 because I expected shorter mate or a draw but this is what tablebases tell me(I used only the KPP vs KP tablebases but if bxa5 is mate in 54(my Fritz6light with tablebases say that it is) then it is clear that a6 is mate in 53,a7 mate in 52,a8Q mate in 51 and the next move mate in 50 because it is clear that the side must push pawns and have no logical alternative). Uri
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.