L Black to move, it is a White win in 95 moves according to Shredder tablebases. Syzygy tablebases confirm the win.

What do DTR (distance to rule) tablebases, that take account of the 50 move rule at every stage of the endgame, say about this particular position?

[StartFlipped "0"]
[FEN "2Q5/8/1K2p3/1P6/8/8/4k3/7q b - - 0 1"]
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    The diagram is incorrect, the bP belongs on e6 not g6 according to the word description (I checked the revision). Also, 95 moves is at least DTZ-incorrect, Syzygy says 35. To OP: Can you double-check and edit? Commented Oct 16, 2023 at 17:32
  • I'm not sure what exactly the question is. Is it what the quickest possible win is, taking the 50 moves rule into account? After all, the Syzygy tablebases do take 50 the 50 moves rule into account, however, they will minimize the time to zeroing (i.e. capture or pawn move) rather than to mate.
    – koedem
    Commented Oct 17, 2023 at 11:50
  • @koedem: DTZ =!= DTR. See chess.stackexchange.com/questions/28520/… for the fine distinctions. Syzygy gives DTZ. Commented Oct 17, 2023 at 15:06
  • Thanks for the reference. So then is the question for which n-move rules this position is still winning and when it turns into a draw?
    – koedem
    Commented Oct 17, 2023 at 15:43


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