I have recently been spending quite a bit of time looking at this position, from a game ArasanX-WaspX on FICS recently;
[d]8/6p1/p4p1k/8/4pNqP/PP2PnP1/3r1PK1/2R2Q2 b - - 0 1
Here Wasp played the sac Nxh4+ and won. Arasan saw the move, but not that it is winning for Black. The difficulty is that once Black has sacrificed, and is down material, moves that draw for Black look good in the search, and Black has numerous opportunities to force a draw: the most direct one is via Kg1 Nf3+ Kg2 Nh4+, but deeper in the search tree there are other opportunities. Arasan doesn't see past this to finding the winning line. I am pretty sure that is a bug, since other engines do find it, at easily reachable depths.
There are some other interesting positions in the variations from this, for example, this one:
[d]8/8/5Qnk/8/4pPq1/PP4P1/3r1P2/2R3K1 b - - 0 1
with bm e3, or this one:
[d]8/8/6nk/6P1/8/PP2p1P1/3r1P2/2R3K1 b - -
where the best move is not the King taking the pawn, but Kh5! (these are not too hard, though).
interesting position
Moderators: hgm, Rebel, chrisw
-
jdart
- Posts: 4366
- Joined: Fri Mar 10, 2006 5:23 am
- Location: http://www.arasanchess.org
-
Frank Quisinsky
- Posts: 6808
- Joined: Wed Nov 18, 2009 7:16 pm
- Location: Gutweiler, Germany
- Full name: Frank Quisinsky
Re: interesting position
Hi Jon,
that's quit clear that you are looking in detail.
All the years Arasan became more strength for endgames but since around 2-3 years it seems that you made a lot for the other playing phases. Never I saw so good Arasan stats for version 22.0, still running in FCP Tourney-2020. Now Arasan is a strong allrounder.
Arasan can find such aggressive moves Wasp find too.
Yesterday I am looking in the 22 Arasan fast lost games.
I think you will find same motives as in the example you give in the game vs. Wasp.
All in all ...
Today Arasan is very complete and can play the different playing phases very equal and is very danger.
A fantastic work you do here!
Nice position ...
Normally Wasp won more with very aggreessive pawns.
Here with an other way, nothing to do with aggressive pawns.
Won game vs. Arasan with such a move in the beginning of endgame ...
I wonder ... the weaknesses from Wasp in the strong playing phase from Arasan.
I will analyze the postion with the current and older Wasp versions.
Very interesting material!
Best for you and keep up the good work around Arasan.
Frank
that's quit clear that you are looking in detail.
All the years Arasan became more strength for endgames but since around 2-3 years it seems that you made a lot for the other playing phases. Never I saw so good Arasan stats for version 22.0, still running in FCP Tourney-2020. Now Arasan is a strong allrounder.
Code: Select all
Games ended with 59 moves
19 Arasan 22.0 BMI2 x64 : 3045.64 263 52.9 37 204 22 139.0 77.6 17.49 3028.44 19.60 37.5
Games endet with 60-79 moves
18 Arasan 22.0 BMI2 x64 : 3037.97 453 49.9 134 184 135 226.0 40.6 25.51 3040.55 26.86 37.9
Games endet with 80-99 moves
20 Arasan 22.0 BMI2 x64 : 3014.87 380 47.0 121 115 144 178.5 30.3 28.17 3043.69 31.02 39.0
Games ended with 100-300 moves
13 Arasan 22.0 BMI2 x64 : 3055.04 424 53.4 83 287 54 226.5 67.7 17.84 3030.90 17.92 38.0
[b]Quiet clear ...[/b]
---
Game end position with 2-6 pieces on board:
19 Arasan 22.0 BMI2 x64 : 3035.88 755 50.0 216 323 216 377.5 42.8 18.12 3037.75 18.74 39.5
Game end position with 7-12 pieces on board:
18 Arasan 22.0 BMI2 x64 : 3038.87 528 51.3 146 250 132 271.0 47.3 19.99 3032.37 21.79 38.9
Game end position with 13-32 pieces on board:
18 Arasan 22.0 BMI2 x64 : 3041.89 237 51.3 13 217 7 121.5 91.6 13.65 3033.24 16.02 36.9
Allrounder ... very equal!!
won59 lost59 draw39 won59w won59b lost59w lost59b
16. Arasan 22.0 BMI2 x64 37 22 53 27 10 11 11Yesterday I am looking in the 22 Arasan fast lost games.
I think you will find same motives as in the example you give in the game vs. Wasp.
All in all ...
Today Arasan is very complete and can play the different playing phases very equal and is very danger.
A fantastic work you do here!
Nice position ...
Normally Wasp won more with very aggreessive pawns.
Here with an other way, nothing to do with aggressive pawns.
Won game vs. Arasan with such a move in the beginning of endgame ...
I wonder ... the weaknesses from Wasp in the strong playing phase from Arasan.
I will analyze the postion with the current and older Wasp versions.
Very interesting material!
Best for you and keep up the good work around Arasan.
Frank
-
jdart
- Posts: 4366
- Joined: Fri Mar 10, 2006 5:23 am
- Location: http://www.arasanchess.org
Re: interesting position
Just another note: I said this is a sac, but it isn't really because the pawn is pinned. However, Black was already down material (2 pawns) and is still down one after Nxh4.
--Jon
--Jon
-
Frank Quisinsky
- Posts: 6808
- Joined: Wed Nov 18, 2009 7:16 pm
- Location: Gutweiler, Germany
- Full name: Frank Quisinsky
Re: interesting position
1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 g5 4.Qxa6 Nh4+ 5.Kg1 gxf4 6.Qxf6+ Ng6
1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 g5 4.Nh3 Nh4+ 5.Kg1 Kh5 6.Qc4 Qxh3
1...Nxh4+ 2.Kg1 Nf3+ 3.Kh1 Qxg3 4.Qh3+ Qxh3+ 5.Nxh3 Kh5 6.Nf4+ Kg4
Different possibilites ...
Wasp 4 need a very long time to see that the position is won, a lot of other engines are faster as Wasp.
All the other engines I try out plays the same logical move 1. ... Nxh4.
The question is indeed why Arasan give allways the 0,00 eval with 3-fold draw.
Must have to do with your 3-fold draw code, maybe Arasan try to reach to hard such 3-fold position and do nothing more if such a position found. I saw that 2 times in FCP Tourney-2020 games for around 8 weeks. Means if 3-fold possible Arasan try to forced the draw. Both games Arasan lost. If you like I can search the games in FCP Tourney-2020 database.
Yes, it seems that is a bug!
Such a bug John found in Wasp for a while.
Hakka won a game very fast, Wasp have 3-fold in eval and do nothing more.
One move later Wasp saw the dilemma directly ...
Engine: Arasan 22.0 BMI2 x64 (768 MB)
by Jon Dart
1.00 0:00 +0.80 1...a5 (136)
1.00 0:00 +0.80 1...a5 (203)
2.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (571)
3.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (698)
4.00 0:00 -0.13 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 a5 (804)
5.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (994)
6.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (1.494)
7.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 Ne5 4.Kg2 Qf3+ 5.Kg1 Ng4 (2.080)
8.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.739)
9.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (6.597)
10.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.679)
11.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.770)
12.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (17.544)
13.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.812)
14.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (29.422)
15.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (43.776)
16.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (55.903)
17.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (73.270)
18.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (102.904)
19.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (141.143)
20.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (197.222)
21.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (302.008)
22.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (550.851) 1782
23.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (969.629) 1740
24.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.260.461) 1757
25.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.704.714) 1759
26.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (2.355.658) 1756
27.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (3.059.859) 1783
28.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (4.440.402) 1801 TB:2
29.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.349.623) 1825 TB:2
30.34 0:03 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (7.163.542) 1817 TB:2
31.34 0:04 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.873.840) 1849 TB:4
32.34 0:05 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.737.004) 1863 TB:6
33.34 0:06 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (13.073.764) 1887 TB:13
34.34 0:08 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (16.220.898) 1903 TB:42
35.34 0:11 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.615.528) 1904 TB:149
36.34 0:15 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (30.608.917) 1921 TB:241
37.34 0:20 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (39.187.140) 1913 TB:262
38.34 0:26 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (51.024.480) 1920 TB:392
39.34 0:33 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (64.925.206) 1919 TB:840
40.34 0:40 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (77.181.295) 1922 TB:997
41.34 0:56 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (107.851.689) 1906 TB:1.825
42.34 1:09 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (132.638.489) 1920 TB:3.767
43.34 1:27 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (168.249.481) 1912 TB:6.269
44.34 1:44 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (200.153.023) 1906 TB:8.195
45.34 2:17 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (261.277.733) 1904 TB:9.999
46.34 2:59 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (339.572.982) 1891 TB:11.445
47.34 3:49 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (432.457.806) 1888 TB:12.704
48.34 4:36 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (523.866.361) 1892 TB:17.329
Best
Frank
1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 g5 4.Nh3 Nh4+ 5.Kg1 Kh5 6.Qc4 Qxh3
1...Nxh4+ 2.Kg1 Nf3+ 3.Kh1 Qxg3 4.Qh3+ Qxh3+ 5.Nxh3 Kh5 6.Nf4+ Kg4
Different possibilites ...
Wasp 4 need a very long time to see that the position is won, a lot of other engines are faster as Wasp.
All the other engines I try out plays the same logical move 1. ... Nxh4.
The question is indeed why Arasan give allways the 0,00 eval with 3-fold draw.
Must have to do with your 3-fold draw code, maybe Arasan try to reach to hard such 3-fold position and do nothing more if such a position found. I saw that 2 times in FCP Tourney-2020 games for around 8 weeks. Means if 3-fold possible Arasan try to forced the draw. Both games Arasan lost. If you like I can search the games in FCP Tourney-2020 database.
Yes, it seems that is a bug!
Such a bug John found in Wasp for a while.
Hakka won a game very fast, Wasp have 3-fold in eval and do nothing more.
One move later Wasp saw the dilemma directly ...
Engine: Arasan 22.0 BMI2 x64 (768 MB)
by Jon Dart
1.00 0:00 +0.80 1...a5 (136)
1.00 0:00 +0.80 1...a5 (203)
2.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (571)
3.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (698)
4.00 0:00 -0.13 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 a5 (804)
5.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (994)
6.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (1.494)
7.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 Ne5 4.Kg2 Qf3+ 5.Kg1 Ng4 (2.080)
8.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.739)
9.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (6.597)
10.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.679)
11.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.770)
12.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (17.544)
13.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.812)
14.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (29.422)
15.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (43.776)
16.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (55.903)
17.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (73.270)
18.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (102.904)
19.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (141.143)
20.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (197.222)
21.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (302.008)
22.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (550.851) 1782
23.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (969.629) 1740
24.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.260.461) 1757
25.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.704.714) 1759
26.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (2.355.658) 1756
27.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (3.059.859) 1783
28.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (4.440.402) 1801 TB:2
29.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.349.623) 1825 TB:2
30.34 0:03 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (7.163.542) 1817 TB:2
31.34 0:04 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.873.840) 1849 TB:4
32.34 0:05 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.737.004) 1863 TB:6
33.34 0:06 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (13.073.764) 1887 TB:13
34.34 0:08 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (16.220.898) 1903 TB:42
35.34 0:11 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.615.528) 1904 TB:149
36.34 0:15 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (30.608.917) 1921 TB:241
37.34 0:20 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (39.187.140) 1913 TB:262
38.34 0:26 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (51.024.480) 1920 TB:392
39.34 0:33 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (64.925.206) 1919 TB:840
40.34 0:40 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (77.181.295) 1922 TB:997
41.34 0:56 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (107.851.689) 1906 TB:1.825
42.34 1:09 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (132.638.489) 1920 TB:3.767
43.34 1:27 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (168.249.481) 1912 TB:6.269
44.34 1:44 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (200.153.023) 1906 TB:8.195
45.34 2:17 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (261.277.733) 1904 TB:9.999
46.34 2:59 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (339.572.982) 1891 TB:11.445
47.34 3:49 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (432.457.806) 1888 TB:12.704
48.34 4:36 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (523.866.361) 1892 TB:17.329
Best
Frank
-
Frank Quisinsky
- Posts: 6808
- Joined: Wed Nov 18, 2009 7:16 pm
- Location: Gutweiler, Germany
- Full name: Frank Quisinsky
Re: interesting position
Engine: Arasan 22.0 BMI2 x64 (768 MB)
by Jon Dart
1.00 0:00 +0.80 1...a5 (136)
1.00 0:00 +0.80 1...a5 (203)
2.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (571)
3.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (698)
4.00 0:00 -0.13 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 a5 (804)
5.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (994)
6.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (1.494)
7.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 Ne5 4.Kg2 Qf3+ 5.Kg1 Ng4 (2.080)
8.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.739)
9.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (6.597)
10.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.679)
11.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.770)
12.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (17.544)
13.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.812)
14.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (29.422)
15.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (43.776)
16.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (55.903)
17.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (73.270)
18.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (102.904)
19.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (141.143)
20.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (197.222)
21.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (302.008)
22.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (550.851) 1782
23.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (969.629) 1740
24.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.260.461) 1757
25.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.704.714) 1759
26.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (2.355.658) 1756
27.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (3.059.859) 1783
28.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (4.440.402) 1801 TB:2
29.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.349.623) 1825 TB:2
30.34 0:03 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (7.163.542) 1817 TB:2
31.34 0:04 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.873.840) 1849 TB:4
32.34 0:05 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.737.004) 1863 TB:6
33.34 0:06 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (13.073.764) 1887 TB:13
34.34 0:08 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (16.220.898) 1903 TB:42
35.34 0:11 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.615.528) 1904 TB:149
36.34 0:15 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (30.608.917) 1921 TB:241
37.34 0:20 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (39.187.140) 1913 TB:262
38.34 0:26 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (51.024.480) 1920 TB:392
39.34 0:33 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (64.925.206) 1919 TB:840
40.34 0:40 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (77.181.295) 1922 TB:997
41.34 0:56 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (107.851.689) 1906 TB:1.825
42.34 1:09 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (132.638.489) 1920 TB:3.767
43.34 1:27 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (168.249.481) 1912 TB:6.269
44.34 1:44 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (200.153.023) 1906 TB:8.195
45.34 2:17 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (261.277.733) 1904 TB:9.999
46.34 2:59 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (339.572.982) 1891 TB:11.445
47.34 3:49 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (432.457.806) 1888 TB:12.704
48.34 4:36 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (523.866.361) 1892 TB:17.329
49.34 5:37 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (639.745.783) 1896 TB:19.966
50.34 6:50 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (778.952.519) 1899 TB:24.636
51.00 14:31 -0.18++ 1...Nxh4+ 2.Kg1 (1.692.334.928) 1941 TB:97.770
51.00 36:11 -0.56++ 1...Nxh4+ 2.Kg1 (4.261.188.438) 1962 TB:305.350
Aha, after a long time (only 1-Core analyzes with 3-4 endgame databases).
But why after ply 50?!
Sure you will find the bug!
by Jon Dart
1.00 0:00 +0.80 1...a5 (136)
1.00 0:00 +0.80 1...a5 (203)
2.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (571)
3.00 0:00 -0.16 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 (698)
4.00 0:00 -0.13 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 a5 (804)
5.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (994)
6.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kg2 Nh4+ (1.494)
7.00 0:00 0.00 1...Nxh4+ 2.Kh2 Nf3+ 3.Kh1 Ne5 4.Kg2 Qf3+ 5.Kg1 Ng4 (2.080)
8.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.739)
9.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (6.597)
10.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.679)
11.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.770)
12.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (17.544)
13.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.812)
14.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (29.422)
15.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (43.776)
16.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (55.903)
17.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (73.270)
18.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (102.904)
19.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (141.143)
20.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (197.222)
21.00 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (302.008)
22.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (550.851) 1782
23.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (969.629) 1740
24.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.260.461) 1757
25.34 0:00 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (1.704.714) 1759
26.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (2.355.658) 1756
27.34 0:01 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (3.059.859) 1783
28.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (4.440.402) 1801 TB:2
29.34 0:02 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (5.349.623) 1825 TB:2
30.34 0:03 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (7.163.542) 1817 TB:2
31.34 0:04 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (8.873.840) 1849 TB:4
32.34 0:05 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (10.737.004) 1863 TB:6
33.34 0:06 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (13.073.764) 1887 TB:13
34.34 0:08 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (16.220.898) 1903 TB:42
35.34 0:11 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (21.615.528) 1904 TB:149
36.34 0:15 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (30.608.917) 1921 TB:241
37.34 0:20 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (39.187.140) 1913 TB:262
38.34 0:26 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (51.024.480) 1920 TB:392
39.34 0:33 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (64.925.206) 1919 TB:840
40.34 0:40 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (77.181.295) 1922 TB:997
41.34 0:56 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (107.851.689) 1906 TB:1.825
42.34 1:09 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (132.638.489) 1920 TB:3.767
43.34 1:27 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (168.249.481) 1912 TB:6.269
44.34 1:44 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (200.153.023) 1906 TB:8.195
45.34 2:17 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (261.277.733) 1904 TB:9.999
46.34 2:59 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (339.572.982) 1891 TB:11.445
47.34 3:49 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (432.457.806) 1888 TB:12.704
48.34 4:36 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (523.866.361) 1892 TB:17.329
49.34 5:37 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (639.745.783) 1896 TB:19.966
50.34 6:50 0.00 1...Nxh4+ 2.Kg1 Nf3+ 3.Kg2 Nh4+ (778.952.519) 1899 TB:24.636
51.00 14:31 -0.18++ 1...Nxh4+ 2.Kg1 (1.692.334.928) 1941 TB:97.770
51.00 36:11 -0.56++ 1...Nxh4+ 2.Kg1 (4.261.188.438) 1962 TB:305.350
Aha, after a long time (only 1-Core analyzes with 3-4 endgame databases).
But why after ply 50?!
Sure you will find the bug!
-
Dann Corbit
- Posts: 12540
- Joined: Wed Mar 08, 2006 8:57 pm
- Location: Redmond, WA USA
Re: interesting position
Do you use null move verification?
I guess that zugzwang might play a role here.
Another thing that might help is to scale pruning a bit using mobility.
I use an s curve to decrease pruning when move choices are very limited and to increase pruning when there are a huge number of possible moves.
I find that it often helps in positions like these.
I guess that zugzwang might play a role here.
Another thing that might help is to scale pruning a bit using mobility.
I use an s curve to decrease pruning when move choices are very limited and to increase pruning when there are a huge number of possible moves.
I find that it often helps in positions like these.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
-
Frank Quisinsky
- Posts: 6808
- Joined: Wed Nov 18, 2009 7:16 pm
- Location: Gutweiler, Germany
- Full name: Frank Quisinsky
Re: interesting position
Hi Dann,
but that is interesting!
Arasan forced 3-fold draw until ply 50 and avoid 3-fold after ply 50??
Maybe it have to do with 50-moves draw rules.
For myself a bug it have to do with the draw rules!
No other engine I checked give a 0,00 eval with a 3-fold line.
Best
Frank
but that is interesting!
Arasan forced 3-fold draw until ply 50 and avoid 3-fold after ply 50??
Maybe it have to do with 50-moves draw rules.
For myself a bug it have to do with the draw rules!
No other engine I checked give a 0,00 eval with a 3-fold line.
Best
Frank
-
jdart
- Posts: 4366
- Joined: Fri Mar 10, 2006 5:23 am
- Location: http://www.arasanchess.org
Re: interesting position
It looks to me like this is due to over-aggressive null move pruning, which makes sense, because some of the key lines (for example after the position I posted with "e3" bm) require one or more "quiet" moves to gain an advantage, and that is the sort of thing null move prunes away. I do use verification but as usual, not at low depths, and I also do a fairly heavy depth reduction on null move. However, a fix is not that straightforward, because tighening it up and fixing problem cases may hurt overall average performance.