Longest Forced Mate Announcement In Computer vs. Computer

[LiquidNitrogenOverclocker]

I am wondering:

What was/is the longest forced checkmate announcement that has been confirmed in an engine match (preferably at longer time controls)?

[Richard Allbert]

In CCT12 this year, HIARCS annouced mate in 130 or similar, but I don't have the game score with HIARCSs' kibitz to give the exact number.

I'm someone who saw it will....!

Richard

[Alexander Schmidt]

I saw a position with a mate in ~250, Yace announced it after a few seconds correctly. Unfortunately I lost the position... If someone has it, pls show it.

BTW It was no tablebase position

[hgm]

Note that such announcements (without tablebases, that is) are seldomly correct, in the sense that the true distance to mate is usually much smaller than what the engines announce. I don't know if that counts, or not. The announcements come about by excessive grafting through hits on over-deep hash entries, and when you have the engine search deeper they sometimes disappear altgether, or are corrected from mate-in-250 to mate-in-50, and then in the next iteration mate-in-14 or something like that.

So the question should be diversified into:
1) What was the longest mate a computer announced, and then could deliver within the announced limit
2) What was the most distant forced mate (against optimal defence) that a computer ever recognized as a mate.

[LiquidNitrogenOverclocker]

Note that such announcements (without tablebases, that is) are seldomly correct, in the sense that the true distance to mate is usually much smaller than what the engines announce. I don't know if that counts, or not. The announcements come about by excessive grafting through hits on over-deep hash entries, and when you have the engine search deeper they sometimes disappear altgether, or are corrected from mate-in-250 to mate-in-50, and then in the next iteration mate-in-14 or something like that.

So the question should be diversified into:
1) What was the longest mate a computer announced, and then could deliver within the announced limit
2) What was the most distant forced mate (against optimal defence) that a computer ever recognized as a mate.

I see where you are going with this. On iteration "n" it found a deep tablebase win that could not be avoided, and this mating distance, D, was much > n. So, there could have been many "true mates" somewhere > n and < D along the way, and this could only be found with deeper searches (which did not occur during the game).

And your item #2 is more in line with my original thinking, and I am interested in seeing both questions answered.

[bob]

Note that such announcements (without tablebases, that is) are seldomly correct, in the sense that the true distance to mate is usually much smaller than what the engines announce. I don't know if that counts, or not. The announcements come about by excessive grafting through hits on over-deep hash entries, and when you have the engine search deeper they sometimes disappear altgether, or are corrected from mate-in-250 to mate-in-50, and then in the next iteration mate-in-14 or something like that.

So the question should be diversified into:
1) What was the longest mate a computer announced, and then could deliver within the announced limit
2) What was the most distant forced mate (against optimal defence) that a computer ever recognized as a mate.

I see where you are going with this. On iteration "n" it found a deep tablebase win that could not be avoided, and this mating distance, D, was much > n. So, there could have been many "true mates" somewhere > n and < D along the way, and this could only be found with deeper searches (which did not occur during the game).

And your item #2 is more in line with my original thinking, and I am interested in seeing both questions answered.

about 12 years ago Crafty announced a mate in 140-something against GM Roman Dzhindi in a 4-program vs 4-gm round robin played on chess.net. Crafty found a way to trade into a KNN vs KP ending. However, Roman didn't go that way and got mated much quicker... There are probably examples of deeper mates when I was using 6 piece EGTBs on ICC but I honestly do not remember any specific examples, it became rather passe' after a while...

[LiquidNitrogenOverclocker]

about 12 years ago Crafty announced a mate in 140-something against GM Roman Dzhindi in a 4-program vs 4-gm round robin played on chess.net. Crafty found a way to trade into a KNN vs KP ending. However, Roman didn't go that way and got mated much quicker... There are probably examples of deeper mates when I was using 6 piece EGTBs on ICC but I honestly do not remember any specific examples, it became rather passe' after a while...

Funny how a mate-in-140 announcement against a GM who was at one time near the top 10 is no big deal



I can still remember the "will a program ever play consistent master-level chess?" debate.

[Steve B]

about 12 years ago Crafty announced a mate in 140-something against GM Roman Dzhindi in a 4-program vs 4-gm round robin played on chess.net. Crafty found a way to trade into a KNN vs KP ending. However, Roman didn't go that way and got mated much quicker... There are probably examples of deeper mates when I was using 6 piece EGTBs on ICC but I honestly do not remember any specific examples, it became rather passe' after a while...

Funny how a mate-in-140 announcement against a GM who was at one time near the top 10 is no big deal



I can still remember the "will a program ever play consistent master-level chess?" debate.

i wonder what are the rules regarding huge mate announcements?
generally ..if no pawn has been moved or piece captured a game would end in a draw after 50 moves
so a 150+ mate announcement really has no meaning at all

are the Fide rules different for rated games in which engines are involved(either human v Engine or Engine v Engine)?

i seem to remember that Fide has modified the 50 move rule to include positions known to take more then 50 moves to deliver mate although i cant recall any of them now

Steve

[hgm]

..if no pawn has been moved or piece captured a game would end in a draw after 50 moves
so a 150+ mate announcement really has no meaning at all

Why do you think there would be no Pawns moved or pieces captured during those 150 moves?

[Steve B]

..if no pawn has been moved or piece captured a game would end in a draw after 50 moves
so a 150+ mate announcement really has no meaning at all

Why do you think there would be no Pawns moved or pieces captured during those 150 moves?

ill rephrase

suppose after a 150 + mate announcment ..somewhere along the way...no pawns are moved or pieces captured in 50 consecutive moves ...
then the game is drawn
any Fide Rules that extend this rule?
Steve