Not logged inRybka Chess Community Forum
Up Topic The Rybka Lounge / Test Positions / First Published
- - By Victor Zakharov (*****) [ru] Date 2012-12-14 15:52
Is there a chance for white to win here? Let's ignore 50 moves rule.

1n1k4/6Q1/5KP1/8/7b/1r6/8/8 w - - 0 1
Parent - - By Fulcrum2000 (****) [nl] Date 2012-12-14 19:28

> Is there a chance for white to win here?

Since you posted it, yes :razz:
Parent - - By Victor Zakharov (*****) [ru] Date 2012-12-14 22:55 Edited 2012-12-14 23:09
He-he :).

It is not easy to find even first 8 moves and to promote the pawn to knight. I am not 100% sure but looks like these are only moves to win.

[FEN "1n1k4/6Q1/5KP1/8/7b/1r6/8/8 w - - 0 1"]
[SetUp "1"]

1. Kf5 Rb5 2. Kg4 Rb4 3. Kf3 Nd7 4. Qh8 Ke7 5. g7 Bf6 6. g8=N Ke6 7. Qh3 Kd6 8. Kg2 Rb2 *

So we have this:
6N1/3n4/3k1b2/8/8/7Q/1r4K1/8 w - - 0 9

And there are only several persons in the world who can check that the following 541 moves leading to mate are optimal.
Attachment: matein549.pgn (8k)
Parent - By irulats (****) [ie] Date 2012-12-14 23:54
Very nice! I can't wait to annoy a good friend by showing him this tomorrow! :lol:
Parent - By Fulcrum2000 (****) [nl] Date 2012-12-15 11:49
So we have a mate in 549 from the position in the OP, nice!.
Parent - By ernest (****) [fr] Date 2012-12-15 18:09

> He-he :).

He-he :) again!

What do the 7-man Lomonosov tablebases have to say for that position?  :cool:
Parent - - By QuiteIgnorant [us] Date 2017-01-18 14:45
Hi all,

I apologize for replying to an ancient thread, but the PGN file above doesn't match that provided at The length for both is 549 moves, but the sequence of moves differs between the two. Is one more correct than the other? More optimal? I really don't know the significance, if any, of a mismatch, so it would be great if someone more knowledgeable could explain.

Parent - By user923005 (****) [us] Date 2017-01-19 18:25
If they are both the same length, then they are both optimal.
If, at any point in the predicted variation, there is more than one choice that leads to mate in the same depth, then there is more than one pv.
With mate in 549, I guess that it is extremely probable that there are several pvs that have 549 moves and lead to mate.
Up Topic The Rybka Lounge / Test Positions / First Published

Powered by mwForum 2.27.4 © 1999-2012 Markus Wichitill