Stalemate Tablebases

[Dries]

Alright. I looked up chess with different armies. Must be very interesting. Kind of sad perhaps that it's seen so rarely.

[Ajedrecista]

Hello Dries:

Your thread is quite interesting! There have been very nice stalemates in actual games and in studies and I enjoy them quite a lot.

My two cents: I have just made up a 7-man example of forced stalemate in one:

[d]6K1/3R2P1/6rk/7p/7P/8/8/8 b - - 0 1

Of course 1.- ..., Rxg7+ {other moves lose}; 2.- Rxg7 {other moves lose} ½-½ {draw by stalemate}.

Regards from Spain.

Ajedrecista.

[Ajedrecista]

Hello again:

I have made up other example just for fun. This time is a stalemate in two. It starts with nine pieces, which is too much for current EGTB, but finishes with seven pieces. It is inspired in Damiano's checkmate pattern but arranging the pieces for a stalemate:

[d]7k/8/5N2/R5R1/r5r1/5p2/5P2/5K2 b - - 0 1

1.- ..., Ra1+ {other moves lose}; 2.- Rxa1 {only move}, Rg1+ {other moves lose}; 3.- Kxg1 {or Rxg1} ½-½ {draw by stalemate}.

There is not a single last move but at least all the last moves lead to stalemate.

It is quite fun to compose these problems but I understand that this is not the point of your thread.

Regards from Spain.

Ajedrecista.

[Dries]

Thanks! I've checked them out. Those are nice examples. The last one is quite an interesting position.

Well, I was kind of wondering how deep a stalemate someone might find under these strict conditions, namely, that the stalemate can be forced and that going for a forced stalemate is the only way to prevent a loss. But that's quite a tough task to undertake.

[hgm]

I suppose you could base a very deep stalemate on a position with a 'rabid Rook'. Where the Rook drives the King with checks through a corridor of pieces, until it reaches a dead end:

[d]7k/p4Q2/P1P1p1P1/1K2P3/1N1P4/1P6/1RBB1PPb/r5NR b - - 0 1

[Dries]

Yeah. I just asked, down at chess.com, if someone could find a stalemate that goes deeper than a stalemate in 2, which is deepest position that I had. I don't see any better idea than to do the thing you describe.

I'm also guessing that stalemate tablebases wouldn't go very deep. Perhaps it would be up to some manual attempt to find the deepest stalemate... if that wouldn't have been done already by someone.

[Dries]

Someone shared a stalemate in 4. Or self-stalemate in 4, since you want to stalemate yourself.

[pgn][Event "EG 1984"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "C J Morse | Selfstalemate in 4 |"]
[Black "-"]
[Result "*"]
[SetUp "1"]
[FEN "8/pp2r1q1/1p6/1pkr4/2p5/1pp5/nK6/1b6 w - - 0 1"]

1. Ka3 b4+ 2. Ka4 b5+ 3. Ka5 b6+ 4. Ka6 = {Black cannot release stalemate} *
[/pgn]

Perhaps those stalemate tablebases weren't such a good idea anyhow. I guess they might be too rare. Perhaps it's a good thing no one actually tried to make them...