Longest Mate

[vb4]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Hope you enjoythis info.

[zullil]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Hope you enjoythis info.

Care to post a link? This is the Internet after all.

[Dirt]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Really a draw by 50 move rule, I'd bet.

[vb4]

Here you go!!

http://rybkaforum.net/cgi-bin/rybkaforu ... 24816;pg=4

Enjoy

[Sven]

Here you go!!

http://rybkaforum.net/cgi-bin/rybkaforu ... 24816;pg=4

Enjoy

Where is the "691"? Can't see it in the thread linked to above.

Sven

[Ajedrecista]

Hello!

Here you go!!

http://rybkaforum.net/cgi-bin/rybkaforu ... 24816;pg=4

Enjoy

Where is the "691"? Can't see it in the thread linked to above.

Sven

Sorry for bumping this topic, but I think that I have found an explanation: I thought that Les had confused moves with half-moves (AKA plies). The number 691 does not appear directly in the link he gave, although there are some download links that contain that info. Here is the link where Les took 691:

http://217.112.41.81/longest_BPP_update.rar

That link was posted on July, 5th; the position with checkmate in 691 half-moves is the next one:

[d]B7/NK6/2P5/8/8/2p5/kb6/8 w - -

The file is named kbnp6kbp.pgn

-----------------------

But I found a longer mate in a link posted on May, 25th:

http://217.112.41.81/longest.rar

I was able to merge all those PGN files into one thanks to this Rybka Forum topic of 2008: George Tsavdaris explained how to create a .bat utility for merge PGN files, and I did exactly the same. Here is the code of Merge_PGN.bat:

Code: Select all

type *.pgn >> All.pgn

Then, I opened the merged file made with Merge_PGN.bat with Notepad and searched one by one, until I found a checkmate in 1090 half-moves:

[d]8/6R1/8/6N1/3k1K2/1B6/7n/7q w - -

The file is named krbnkqn.pgn

I think that this explains everything. Have fun!

Regards from Spain.

Ajedrecista.

[rbarreira]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Really a draw by 50 move rule, I'd bet.

A lame rule that should disappear or be changed, at least for computer games.

[Arpad Rusz]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Really a draw by 50 move rule, I'd bet.

A lame rule that should disappear or be changed, at least for computer games.

I agree. As I see it, the 50 moves rule is not a basic game rule for chess but only a tournament rule.
There is already a domain were the 50 moves rule was never accepted: endgame study composition.

[syzygy]

Then, I opened the merged file made with Merge_PGN.bat with Notepad and searched one by one, until I found a checkmate in 1090 half-moves:

[d]8/6R1/8/6N1/3k1K2/1B6/7n/7q w - -

I was thinking this can't be right, since the longest win in this tablebase is well-known to be 517 (full) moves (see e.g. here, item 316). However, that is 517 moves to conversion. Maximal distance to mate is apparently again quite a few moves more (and achieved by a somewhat different position).

[syzygy]

Just letting those of you who are not aware of it but the latest and longest distance to mate is now Mate in 691 !! Thats right you heard 691.

Really a draw by 50 move rule, I'd bet.

A lame rule that should disappear or be changed, at least for computer games.

I agree. As I see it, the 50 moves rule is not a basic game rule for chess but only a tournament rule.
There is already a domain were the 50 moves rule was never accepted: endgame study composition.

I agree that 50 moves is arbitrary, but also computer games must end at some point. Three-fold repetition doesn't really cut it when you get to drawish endgames with very few pawns left. Any other fixed number other than 50 is arbitrary as well. Letting the number of moves depend on available egtb knowledge seems silly to me. At least the 50-move rule is well-established and chess programmers (and tablebase generators) can prepare for it if they choose to do so.

Of course these arguments do not apply to compositions.