Discussion of anything and everything relating to chess playing software and machines.
Moderators: hgm , Rebel , chrisw
Mike S.
Posts: 1480 Joined: Thu Mar 09, 2006 5:33 am
Post
by Mike S. » Sun Apr 24, 2011 3:54 am
[D]knR3b1/1p2pp2/PP1prp2/2p1b3/2P1K3/8/8/7n w - - 0 2
2.Rxb8+!
Sacrifice of the last piece, zugzwang, stalemate... Engines seem to find this either immediatly or never. I'm almost sure it is the old nullmove/zugzwang problem. Nothing new; I'm posting it mainly because I thought it is somewhat unusual, with more material on the board than in other examples. Which may be part of the problem here for engines which would turn off nullmove depending from material, but there's too much yet. But
after Rxb8+, all engines I tried saw the rest immediatly.
Code: Select all
[Event "Study (Schach 1976)"]
[Site "?"]
[Date "1976.??.??"]
[Round "?"]
[White "Roberts Skuja"]
[Black "White to draw"]
[Result "1/2-1/2"]
[Annotator "User"]
[SetUp "1"]
[FEN "knR3b1/1p2pp2/PP1prp2/2p1b3/2P1K3/8/8/7n w - - 0 2"]
[PlyCount "5"]
2. Rxb8+ $1 {(I have omitted 1.Rc7-c8+ Nc6-b8.)} Kxb8 3. a7+ Ka8 (3... Kc8 4.
a8=Q+ Kd7 5. Qxb7+ Kd8 6. Qc7+ Ke8 7. Qc8#) 4. Kd5 $11 {Each of Black's move
causes stalemate.} 1/2-1/2
Regards, Mike
Arpad Rusz
Posts: 273 Joined: Sat Apr 17, 2010 2:34 pm
Location: Budapest
Post
by Arpad Rusz » Sun Apr 24, 2011 10:41 am
Another unavoidable stalemate (Rusz, Humor Tourney - 2004):
[D]8/8/8/5N2/5pp1/5p2/pKppprpn/1brqnkb1 w - - 0 1
Thematic try: 1. Ka1? Nd3 2.Ne3+! Ke1 3.Nxg2+! Kf1 4.Ne3+ perpetual check or stalemate. But 1...g3! wins!
The solution: 1. Ng3+! fxg3 2. Ka1! reciprocal zugzwang
[D]8/8/8/8/6p1/5pp1/p1ppprpn/Kbrqnkb1 b - - 0 2
2...Nd3 stalemate
Mike S.
Posts: 1480 Joined: Thu Mar 09, 2006 5:33 am
Post
by Mike S. » Sun Apr 24, 2011 5:22 pm
Great! Thank you. I'll put it into my database of interesting positions.
Regards, Mike
F. Bluemers
Posts: 868 Joined: Thu Mar 09, 2006 11:21 pm
Location: Nederland
Post
by F. Bluemers » Sun Apr 24, 2011 6:30 pm
Arpad Rusz wrote: Another unavoidable stalemate (Rusz, Humor Tourney - 2004):
[D]8/8/8/5N2/5pp1/5p2/pKppprpn/1brqnkb1 w - - 0 1
Thematic try: 1. Ka1? Nd3 2.Ne3+! Ke1 3.Nxg2+! Kf1 4.Ne3+ perpetual check or stalemate. But 1...g3! wins!
The solution: 1. Ng3+! fxg3 2. Ka1! reciprocal zugzwang
[D]8/8/8/8/6p1/5pp1/p1ppprpn/Kbrqnkb1 b - - 0 2
2...Nd3 stalemate
Nice,but too easy for Dirty
Code: Select all
56 0.00 23.9M 0:10.29 Ng3+ fxg3 Ka1 Nd3
55 0.00 23.9M 0:10.29 Ng3+ fxg3 Ka1 Nd3
55 0.00 19.8M 0:08.56 Ng3+ fxg3 Ka1 Nd3
54 0.00 19.8M 0:08.56 Ng3+ fxg3 Ka1 Nd3
54 0.00 16.4M 0:07.08 Ng3+ fxg3 Ka1 Nd3
53 0.00 16.4M 0:07.08 Ng3+ fxg3 Ka1 Nd3
53 0.00 13.5M 0:05.86 Ng3+ fxg3 Ka1 Nd3
52 0.00 13.5M 0:05.86 Ng3+ fxg3 Ka1 Nd3
52 0.00 11.1M 0:04.83 Ng3+ fxg3 Ka1 Nd3
51 0.00 11.1M 0:04.83 Ng3+ fxg3 Ka1 Nd3
51 0.00 9.2M 0:04.02 Ng3+ fxg3 Ka1 Nd3
50 0.00 9.2M 0:04.02 Ng3+ fxg3 Ka1 Nd3
50 0.00 7.6M 0:03.33 Ng3+ fxg3 Ka1 Nd3
49 0.00 7.6M 0:03.33 Ng3+ fxg3 Ka1 Nd3
49 0.00 6.2M 0:02.74 Ng3+ fxg3 Ka1 Nd3
48 0.00 6.2M 0:02.74 Ng3+ fxg3 Ka1 Nd3
48 0.00 5.1M 0:02.27 Ng3+ fxg3 Ka1 Nd3
47 0.00 5.1M 0:02.27 Ng3+ fxg3 Ka1 Nd3
47 0.00 4.2M 0:01.87 Ng3+ fxg3 Ka1 Nd3
46 0.00 4.2M 0:01.87 Ng3+ fxg3 Ka1 Nd3
46 0.00 3.4M 0:01.54 Ng3+ fxg3 Ka1 Nd3
45 0.00 3.4M 0:01.54 Ng3+ fxg3 Ka1 Nd3
45 0.00 2.8M 0:01.28 Ng3+ fxg3 Ka1 Nd3
44 0.00 2.8M 0:01.28 Ng3+ fxg3 Ka1 Nd3
44 0.00 2.3M 0:01.06 Ng3+ fxg3 Ka1 Nd3
43 0.00 2.3M 0:01.06 Ng3+ fxg3 Ka1 Nd3
43 0.00 1.9M 0:00.87 Ng3+ fxg3 Ka1 Nd3
42 0.00 1.9M 0:00.87 Ng3+ fxg3 Ka1 Nd3
42 0.00 1.5M 0:00.71 Ng3+ fxg3 Ka1 Nd3
41 0.00 1.5M 0:00.71 Ng3+ fxg3 Ka1 Nd3
41 0.00 1.2M 0:00.59 Ng3+ fxg3 Ka1 Nd3
40 0.00 1.2M 0:00.59 Ng3+ fxg3 Ka1 Nd3
40 0.00 993775 0:00.50 Ng3+ fxg3 Ka1 Nd3
39 0.00 993263 0:00.50 Ng3+ fxg3 Ka1 Nd3
39 0.00 806958 0:00.42 Ng3+ fxg3 Ka1 Nd3
38 0.00 806445 0:00.42 Ng3+ fxg3 Ka1 Nd3
38 0.00 654420 0:00.35 Ng3+ fxg3 Ka1 Nd3
37 0.00 653907 0:00.35 Ng3+ fxg3 Ka1 Nd3
37 0.00 530815 0:00.29 Ng3+ fxg3 Ka1 Nd3
36 0.00 530303 0:00.29 Ng3+ fxg3 Ka1 Nd3
36 0.00 430145 0:00.25 Ng3+ fxg3 Ka1 Nd3
35 0.00 429634 0:00.25 Ng3+ fxg3 Ka1 Nd3
35 0.00 348487 0:00.21 Ng3+ fxg3 Ka1 Nd3
34 0.00 347989 0:00.21 Ng3+ fxg3 Ka1 Nd3
34 0.00 282499 0:00.18 Ng3+ fxg3 Ka1 Nd3
33 0.00 282002 0:00.18 Ng3+ fxg3 Ka1 Nd3
33 0.00 228735 0:00.17 Ng3+ fxg3 Ka1 Nd3
32 0.00 228281 0:00.17 Ng3+ fxg3 Ka1 Nd3
32 0.00 188435 0:00.14 Ng3+ fxg3 Ka1 Nd3
31 0.00 187985 0:00.14 Ng3+ fxg3 Ka1 Nd3
31 0.00 158945 0:00.12 Ng3+ fxg3 Ka1 Nd3
30 0.00 158534 0:00.12 Ng3+ fxg3 Ka1 Nd3
30 0.00 130798 0:00.11 Ng3+ fxg3 Ka1 Nd3
29 0.00 130416 0:00.09 Ng3+ fxg3 Ka1 Nd3
29 0.00 106796 0:00.09 Ng3+ fxg3 Ka1 Nd3
28 0.00 106415 0:00.09 Ng3+ fxg3 Ka1 Nd3
28 0.00 86657 0:00.07 Ng3+ fxg3 Ka1 Nd3
27 0.00 86329 0:00.07 Ng3+ fxg3 Ka1 Nd3
27 0.00 70377 0:00.06 Ng3+ fxg3 Ka1 Nd3
26 0.00 70064 0:00.06 Ng3+ fxg3 Ka1 Nd3
26 0.00 57086 0:00.06 Ng3+ fxg3 Ka1 Nd3
25 0.00 56805 0:00.06 Ng3+ fxg3 Ka1 Nd3
25 0.00 46171 0:00.04 Ng3+ fxg3 Ka1 Nd3
24 0.00 45910 0:00.04 Ng3+ fxg3 Ka1 Nd3
24 0.00 37747 0:00.04 Ng3+ fxg3 Ka1 Nd3
23 0.00 37489 0:00.04 Ng3+ fxg3 Ka1 Nd3
23 0.00 30888 0:00.03 Ng3+ fxg3 Ka1 Nd3
22 0.00 30665 0:00.03 Ng3+ fxg3 Ka1 Nd3
22 0.00 25044 0:00.03 Ng3+ fxg3 Ka1 Nd3
21 0.00 24841 0:00.03 Ng3+ fxg3 Ka1 Nd3
21 0.00 20074 0:00.03 Ng3+ fxg3 Ka1 Nd3
20 0.00 19897 0:00.03 Ng3+ fxg3 Ka1 Nd3
20 0.00 15905 0:00.03 Ng3+ fxg3 Ka1 Nd3
19 0.00 15754 0:00.03 Ng3+ fxg3 Ka1 Nd3
19 0.00 12721 0:00.01 Ng3+ fxg3 Ka1 Nd3
18 0.00 12571 0:00.01 Ng3+ fxg3 Ka1 Nd3
18 0.00 10050 0:00.01 Ng3+ fxg3 Ka1 Nd3
17 0.00 9925 0:00.01 Ng3+ fxg3 Ka1 Nd3
17 0.00 7978 0:00.01 Ng3+ fxg3 Ka1 Nd3
16 0.00 7868 0:00.01 Ng3+ fxg3 Ka1 Nd3
16 0.00 6276 0:00.01 Ng3+ fxg3 Ka1 Nd3
15 0.00 6187 0:00.01 Ng3+ fxg3 Ka1 Nd3
15 0.00 4919 0:00.01 Ng3+ fxg3 Ka1 Nd3
14 0.00 4837 0:00.01 Ng3+ fxg3 Ka1 Nd3
14 0.00 3801 0:00.01 Ng3+ fxg3 Ka1 Nd3
13 0.00 3722 0:00.01 Ng3+ fxg3 Ka1 Nd3
13 0.00 2928 0:00.01 Ng3+ fxg3 Ka1 Nd3
12 0.00 2858 0:00.01 Ng3+ fxg3 Ka1 Nd3
12 0.00 2309 0:00.01 Ng3+ fxg3 Ka1 Nd3
11 0.00 2254 0:00.01 Ng3+ fxg3 Ka1 Nd3
11 0.00 1831 0:00.01 Ng3+ fxg3 Ka1 Nd3
10 0.00 1791 0:00.01 Ng3+ fxg3 Ka1 Nd3
10 0.00 1494 0:00.01 Ng3+ fxg3 Ka1 Nd3
9 0.00 1458 0:00.01 Ng3+ fxg3 Ka1 Nd3
9 0.00 1144 0:00.01 Ng3+ fxg3 Ka1 Nd3
8 0.00 1107 0:00.01 Ng3+ fxg3 Ka1 Nd3
8 0.00 904 0:00.01 Ng3+ fxg3 Ka1 Nd3
7 0.00 871 0:00.01 Ng3+ fxg3 Ka1 Nd3
7 0.00 683 0:00.01 Ng3+ fxg3 Ka1 Nd3
6 0.00 661 0:00.00 Ng3+ fxg3 Ka1 Nd3
6 0.00 560 0:00.00 Ng3+ fxg3 Ka1 Nd3
5 0.00 551 0:00.00 Ng3+ fxg3 Ka1 Nd3
5 0.00 521 0:00.00 Ng3+ fxg3 Ka1 Nd3
4 0.00 511 0:00.00 Ng3+ fxg3 Ka1 Nd3
4 0.00 481 0:00.00 Ng3+ fxg3 Ka1 Nd3
3 0.00 472 0:00.00 Ng3+ fxg3 Ka1 Nd3
3 0.00 454 0:00.00 Ng3+ fxg3 Ka1 Nd3
3 -62.37 355 0:00.00 Ka1 Nd3 Ng3+ fxg3
2 -55.82 312 0:00.00 Ka1 Nd3
2 -55.82 301 0:00.00 Ka1 Nd3
2 -55.82 300 0:00.00 Ka1 Nd3
2 -55.82 154 0:00.00 Ka1 Nd3
1 -55.05 151 0:00.00 Ka1
Seems it can't crack the other one though
bob
Posts: 20943 Joined: Mon Feb 27, 2006 7:30 pm
Location: Birmingham, AL
Post
by bob » Mon Apr 25, 2011 7:22 pm
Arpad Rusz wrote: Another unavoidable stalemate (Rusz, Humor Tourney - 2004):
[D]8/8/8/5N2/5pp1/5p2/pKppprpn/1brqnkb1 w - - 0 1
Thematic try: 1. Ka1? Nd3 2.Ne3+! Ke1 3.Nxg2+! Kf1 4.Ne3+ perpetual check or stalemate. But 1...g3! wins!
The solution: 1. Ng3+! fxg3 2. Ka1! reciprocal zugzwang
[D]8/8/8/8/6p1/5pp1/p1ppprpn/Kbrqnkb1 b - - 0 2
2...Nd3 stalemate
second one is not so good. Why would black want to stalemate white???
What am I missing?
Never mind.
Black is going toward bottom of board and has no moves except for knight...
Last edited by bob on Mon Apr 25, 2011 7:46 pm, edited 2 times in total.
Mike S.
Posts: 1480 Joined: Thu Mar 09, 2006 5:33 am
Post
by Mike S. » Mon Apr 25, 2011 7:34 pm
bob wrote: Why would black want to stalemate white???
He has no choice!
Maybe the 1st Rusz position is suitable to check for bugs? But it is only 4 plies and I did not find an engine which has nullmove/zugzwang problems here. Anyway funny to look at, for humans.
Regards, Mike
Arpad Rusz
Posts: 273 Joined: Sat Apr 17, 2010 2:34 pm
Location: Budapest
Post
by Arpad Rusz » Mon Apr 25, 2011 11:41 pm
I have composed a new position:
[D]8/8/8/1p6/2Q1p3/2K3pp/p1p1pprb/k2brqnn w - - 0 1
Draw
F. Bluemers
Posts: 868 Joined: Thu Mar 09, 2006 11:21 pm
Location: Nederland
Post
by F. Bluemers » Mon Apr 25, 2011 11:47 pm
Arpad Rusz wrote: I have composed a new position:
[D]8/8/8/1p6/2Q1p3/2K3pp/p1p1pprb/k2brqnn w - - 0 1
Draw
Code: Select all
31 0.00 39.2M 0:20.71 Kd2 Nf3+ Kc1 bxc4
31 0.00 31.5M 0:16.75 Kd2 Nf3+ Kc1 bxc4
30 0.00 27.8M 0:14.64 Kd2 Nf3+ Kc1 bxc4
30 0.00 22.1M 0:11.70 Kd2 Nf3+ Kc1 bxc4
29 0.00 19.5M 0:10.29 Kd2 Nf3+ Kc1 bxc4
29 0.00 15.5M 0:08.23 Kd2 Nf3+ Kc1 bxc4
28 0.00 13.8M 0:07.33 Kd2 Nf3+ Kc1 bxc4
28 0.00 10.7M 0:05.75 Kd2 Nf3+ Kc1 bxc4
27 0.00 9.6M 0:05.21 Kd2 Nf3+ Kc1 bxc4
27 0.00 7.5M 0:04.15 Kd2 Nf3+ Kc1 bxc4
26 0.00 6.8M 0:03.72 Kd2 Nf3+ Kc1 bxc4
26 0.00 5.3M 0:02.96 Kd2 Nf3+ Kc1 bxc4
25 0.00 4.8M 0:02.71 Kd2 Nf3+ Kc1 bxc4
25 0.00 3.7M 0:02.10 Kd2 Nf3+ Kc1 bxc4
24 0.00 3.4M 0:01.90 Kd2 Nf3+ Kc1 bxc4
24 0.00 2.6M 0:01.49 Kd2 Nf3+ Kc1 bxc4
23 0.00 2.4M 0:01.37 Kd2 Nf3+ Kc1 bxc4
23 0.00 1.8M 0:01.07 Kd2 Nf3+ Kc1 bxc4
22 0.00 1.6M 0:00.96 Kd2 Nf3+ Kc1 bxc4
22 0.00 1.2M 0:00.76 Kd2 Nf3+ Kc1 bxc4
21 0.00 1.1M 0:00.70 Kd2 Nf3+ Kc1 bxc4
21 0.00 846478 0:00.54 Kd2 Nf3+ Kc1 bxc4
20 0.00 758190 0:00.49 Kd2 Nf3+ Kc1 bxc4
20 0.00 573686 0:00.39 Kd2 Nf3+ Kc1 bxc4
19 0.00 512479 0:00.35 Kd2 Nf3+ Kc1 bxc4
19 0.00 389092 0:00.29 Kd2 Nf3+ Kc1 bxc4
18 0.00 352872 0:00.26 Kd2 Nf3+ Kc1 bxc4
18 0.00 256187 0:00.21 Kd2 Nf3+ Kc1 bxc4
17 0.00 224474 0:00.18 Kd2 Nf3+ Kc1 bxc4
17 0.00 157749 0:00.15 Kd2 Nf3+ Kc1 bxc4
16 0.00 148251 0:00.14 Kd2 Nf3+ Kc1 bxc4
16 0.00 107356 0:00.10 Kd2 Nf3+ Kc1 bxc4
15 0.00 101373 0:00.10 Kd2 Nf3+ Kc1 bxc4
15 0.00 67229 0:00.09 Kd2 Nf3+ Kc1 bxc4
14 0.00 63453 0:00.09 Kd2 Nf3+ Kc1 bxc4
14 0.00 42486 0:00.07 Kd2 Nf3+ Kc1 bxc4
13 0.00 40435 0:00.06 Kd2 Nf3+ Kc1 bxc4
13 0.00 31895 0:00.06 Kd2 Nf3+ Kc1 bxc4
12 0.00 30587 0:00.06 Kd2 Nf3+ Kc1 bxc4
12 0.00 23510 0:00.06 Kd2 Nf3+ Kc1 bxc4
11 0.00 22577 0:00.04 Kd2 Nf3+ Kc1 bxc4
11 0.00 18256 0:00.04 Kd2 Nf3+ Kc1 bxc4
10 0.00 17655 0:00.04 Kd2 Nf3+ Kc1 bxc4
10 0.00 15295 0:00.04 Kd2 Nf3+ Kc1 bxc4
9 0.00 14759 0:00.04 Kd2 Nf3+ Kc1 bxc4
9 0.00 13267 0:00.04 Kd2 Nf3+ Kc1 bxc4
8 0.00 13035 0:00.03 Kd2 Nf3+ Kc1 bxc4
8 0.00 11970 0:00.03 Kd2 Nf3+ Kc1 bxc4
7 0.00 11809 0:00.03 Kd2 Nf3+ Kc1 bxc4
7 0.00 11202 0:00.03 Kd2 Nf3+ Kc1 bxc4
6 0.00 11109 0:00.03 Kd2 Nf3+ Kc1 bxc4
6 0.00 10891 0:00.03 Kd2 Nf3+ Kc1 bxc4
5 0.00 10822 0:00.03 Kd2 Nf3+ Kc1 bxc4
5 0.00 10736 0:00.03 Kd2 Nf3+ Kc1 bxc4
5 -51.32 9222 0:00.03 Qxb5 c1=Q+ Kb4 Kb2 Ka5+ Kc3 Qb4+ Kc2
4 -50.84 7938 0:00.01 Qxb5 c1=Q+ Kb4 Kb2 Ka5+ Kc3
4 -50.84 4123 0:00.01 Qxb5 c1=Q+ Kb4 Kb2 Ka5+ Kc3
3 -52.38 2207 0:00.01 Qxb5 c1=Q+ Kd4 Qc8
3 -52.38 895 0:00.01 Qxb5 c1=Q+ Kd4 Qc8
2 -54.67 751 0:00.01 Qxb5 c1=Q+ Kd4
2 -54.67 731 0:00.01 Qxb5 c1=Q+ Kd4
2 -54.67 730 0:00.00 Qxb5 c1=Q+ Kd4
2 -54.67 396 0:00.00 Qxb5 c1=Q+ Kd4
2 -55.28 328 0:00.00 Qxe4 c1=Q+ Kd4
2 -55.75 251 0:00.00 Qd4 c1=Q+ Kb4+ Qb2+ Kc5
1 -52.49 207 0:00.00 Qd4
correct?
Arpad Rusz
Posts: 273 Joined: Sat Apr 17, 2010 2:34 pm
Location: Budapest
Post
by Arpad Rusz » Tue Apr 26, 2011 12:26 am
Yes, it is correct, 1.Kd2 is the first move. The main line is 1.Kd2! bxc4 2.Kc1 reciprocal zugzwang
[D]8/8/8/8/2p1p3/6pp/p1p1pprb/k1Kbrqnn b - - 0 2
2...Nf3/c3/e3 stalemate
Arpad Rusz
Posts: 273 Joined: Sat Apr 17, 2010 2:34 pm
Location: Budapest
Post
by Arpad Rusz » Tue Apr 26, 2011 12:41 am
The following study is a good test position for engines.
B.Sidorov (64-Shakmatnoe Obozrenie, 1982)
[D]8/8/1p6/1pp5/n1p5/1pp5/brrp1pK1/nqbk4 w - - 0 1
Draw