83 nice Testpositions (Long and big post).

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Uri Blass
Posts: 10915
Joined: Thu Mar 09, 2006 12:37 am
Location: Tel-Aviv Israel

Re: 83 nice Testpositions (Long and big post).

Post by Uri Blass »

3.Kf8 instead of 3.Bf7 is winning

New game
8/4K2p/6pr/7k/1pB2Pp1/p5P1/8/8 w - - 0 1

Analysis by Rybka 2.3.2a 32-bit :

3.Bc4-d5 g6-g5
³ (-0.67) Depth: 5 00:00:15
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5
³ (-0.44) Depth: 6 00:00:15 1kN
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5 Kh5-h6
³ (-0.31) Depth: 7 00:00:15 1kN
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6
= (0.00) Depth: 8 00:00:15 1kN
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 h7xg6 7.Ke7-f6
= (0.00) Depth: 9 00:00:15 1kN
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 h7xg6 7.Ke7-f6 Kh6-h7
= (0.06) Depth: 10 00:00:15 2kN
3.Bc4-d5 g6-g5 4.Bd5-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 a3-a2 7.Bf7xa2 Kh6xg6 8.Ba2-d5 h7-h6 9.Ke7-e6
= (-0.03) Depth: 11 00:00:15 9kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-e5+
± (1.24) Depth: 11 00:00:15 13kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 12 00:00:15 16kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 13 00:00:15 17kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 14 00:00:15 18kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 15 00:00:15 21kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 16 00:00:16 25kN
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 17 00:00:16 31kN, tb=1
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 18 00:00:16 40kN, tb=2
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 19 00:00:16 54kN, tb=4
3.Bc4-f7 b4-b3 4.Bf7xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 a3-a2 7.f5xg6 a2-a1Q 8.g6-g7+ Kh5-h6 9.g7-g8Q Qa1-f6+
= (0.00) Depth: 20 00:00:17 76kN, tb=5
3.Ke7-f8 b4-b3 4.Bc4xb3 a3-a2 5.Bb3xa2 g6-g5 6.Ba2-f7+
+- (2.50) Depth: 20 00:00:17 120kN, tb=6
3.Ke7-f8 b4-b3 4.Bc4xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 Kh5-h6 7.f5xg6 h7xg6 8.Kf8-g8 a3-a2 9.Bf7xa2 Kh6-h5
+- (4.75) Depth: 20 00:00:19 164kN, tb=31
3.Ke7-f8 b4-b3 4.Bc4xb3 g6-g5 5.Bb3-f7+ Rh6-g6 6.f4-f5 Kh5-h6 7.f5xg6 h7xg6 8.Kf8-g8 a3-a2 9.Bf7xa2 Kh6-h5
+- (4.75) Depth: 21 00:00:20 174kN, tb=34
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 a3-a2 6.f5xg6 h7xg6 7.Bf7xa2 Kh5-h6 8.Kf8-g8 b4-b3 9.Ba2xb3 Kh6-h5
+- (4.87) Depth: 22 00:00:34 1407kN, tb=100
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 a3-a2 6.f5xg6 h7xg6 7.Bf7xa2 Kh5-h6 8.Kf8-g8 b4-b3 9.Ba2xb3 Kh6-h5
+- (7.37) Depth: 23 00:00:35 1441kN, tb=158
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 a3-a2 6.f5xg6 h7xg6 7.Bf7xa2 Kh5-h6 8.Kf8-g8 b4-b3 9.Ba2xb3 Kh6-h5 10.Bb3-c2 Kh5-h6 11.Kg8-f7 Kh6-h7 12.Bc2xg6+ Kh7-h6 13.Bg6-f5
+- (#25) Depth: 23 00:00:36 1717kN, tb=182
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 a3-a2 6.f5xg6 h7xg6 7.Bf7xa2 Kh5-h6 8.Kf8-g8 b4-b3 9.Ba2xb3 Kh6-h5 10.Bb3-c2 Kh5-h6 11.Kg8-f7 Kh6-h7 12.Bc2xg6+ Kh7-h6 13.Bg6-f5 Kh6-h5 14.Kf7-f6 Kh5-h6 15.Bf5xg4 Kh6-h7 16.Kf6xg5 Kh7-g7 17.Bg4-e6 Kg7-f8 18.Kg5-f6 Kf8-e8
+- (#25) Depth: 24 00:00:43 2543kN, tb=391
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 a3-a2 6.f5xg6 h7xg6 7.Bf7xa2 Kh5-h6 8.Kf8-g8 b4-b3 9.Ba2xb3 Kh6-h5 10.Bb3-c2 Kh5-h6 11.Kg8-f7 Kh6-h7 12.Bc2xg6+ Kh7-h6 13.Bg6-f5 Kh6-h5 14.Kf7-f6 Kh5-h6 15.Bf5xg4 Kh6-h7 16.Kf6xg5 Kh7-g7 17.Bg4-e6 Kg7-f8 18.Kg5-f6 Kf8-e8
+- (#25) Depth: 25 00:00:50 3780kN, tb=983
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 h7xg6 7.Kf8-g8 b4-b3 8.Bf7xb3 a3-a2 9.Bb3xa2 Kh6-h5 10.Kg8-f7 Kh5-h6 11.Ba2-b1 Kh6-h7 12.Bb1xg6+ Kh7-h6 13.Bg6-f5 Kh6-h5 14.Kf7-f6 Kh5-h6 15.Bf5xg4 Kh6-h7 16.Kf6xg5 Kh7-g7 17.Bg4-e6 Kg7-f8 18.Kg5-f6 Kf8-e8
+- (#25) Depth: 26 00:01:22 5888kN, tb=41623
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 h7xg6 7.Kf8-g8 b4-b3 8.Bf7xb3 a3-a2 9.Bb3xa2 Kh6-h5 10.Kg8-f7 Kh5-h6 11.Ba2-b1 Kh6-h7 12.Bb1xg6+ Kh7-h6 13.Bg6-f5 Kh6-h5 14.Kf7-f6 Kh5-h6 15.Bf5xg4 Kh6-h7 16.Kf6xg5 Kh7-g7 17.Bg4-e6 Kg7-f8 18.Kg5-f6 Kf8-e8
+- (#25) Depth: 27 00:01:37 8274kN, tb=44052
3.Ke7-f8 g6-g5 4.Bc4-f7+ Rh6-g6 5.f4-f5 Kh5-h6 6.f5xg6 h7xg6 7.Kf8-g8 b4-b3 8.Bf7xb3 a3-a2 9.Bb3xa2 Kh6-h5 10.Kg8-f7 Kh5-h6 11.Ba2-b1 Kh6-h7 12.Bb1xg6+ Kh7-h6 13.Bg6-f5 Kh6-h5 14.Kf7-f6 Kh5-h6 15.Bf5xg4 Kh6-h7 16.Kf6xg5 Kh7-g7 17.Bg4-e6 Kg7-f8 18.Kg5-f6 Kf8-e8
+- (#25) Depth: 28 00:02:10 11618kN, tb=68072

(, 19.08.2007)
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ardee

Re: 83 nice Testpositions (Long and big post).

Post by ardee »

[quote="Uri Blass"]3.Kf8 instead of 3.Bf7 is winning

You're right! Thanks!!
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Vinvin
Posts: 5300
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: 83 nice Testpositions (Long and big post).

Post by Vinvin »

ardee wrote:Please forgive my ignorance, but here's one more from that list that I cannot get, even with help from programs:

[d]2b1r3/r2ppN2/8/1p1p1k2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1

White can reportedly draw via 1. Nd6+, but after 1. ... exd6 I don't see the draw. (Don't see a way to keep checking or to block Black's other Rook in or to promote a pawn, even beginning with 2. a3).

Got more analysis for this one? For some of the other tactical ones that strong programs like Rybka cannot get?
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Pos"]
[Black "?"]
[Result "1/2-1/2"]
[SetUp "1"]
[FEN "2b1r3/r2ppN2/8/1p1p1k2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1"]
[PlyCount "31"]

{Building a fortress} 1. Nd6+ $1 exd6 2. Rf3+ Kg5 3. Rg3+ Kf6 4. Rf3+ Ke7 5.
Re3+ Kd8 6. Rxe8+ Kxe8 7. a3 Ra8 8. Kd2 Bb7 9. Ke2 Kf7 10. Kf1 Rh8 11. Kg1 Kf6
12. f3 Kf5 13. g3 Re8 14. Kf2 Re7 15. Kf1 Rh7 16. Kg2 1/2-1/2
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Vinvin
Posts: 5300
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: 83 nice Testpositions (Long and big post).

Post by Vinvin »

ardee wrote:Another one whose "solution" I am not yet convinced of:

[d]r1b1r1k1/1p1nnpp1/pq1Bp2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 0 1

I don't see White's advantage after, for example, 1. Bc7 Qc6 2. Rxf7 Kxf7 3. Nd6+ (3. Bh5+ Kg8 4. Bxe8 Qxe4) 3... Kg8 4. Nxe8 Nf5 5. Qg6 Qc3 6. Qxe6+ Kh8

Anybody?
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007
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ardee

Re: 83 nice Testpositions (Long and big post).

Post by ardee »

Vinvin wrote:
ardee wrote:Another one whose "solution" I am not yet convinced of:

[d]r1b1r1k1/1p1nnpp1/pq1Bp2p/8/4N3/6Q1/2PRB1PP/5R1K w - - 0 1

I don't see White's advantage after, for example, 1. Bc7 Qc6 2. Rxf7 Kxf7 3. Nd6+ (3. Bh5+ Kg8 4. Bxe8 Qxe4) 3... Kg8 4. Nxe8 Nf5 5. Qg6 Qc3 6. Qxe6+ Kh8

Anybody?
Look at first game (first diagram) here : http://www.chessbase.com/newsdetail.asp?newsid=4007
Wow, that's very impressive. I had the right line for several moves but missed the winning exchange sacrifice and subsequent attacking idea. Thanks!
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ardee

Re: 83 nice Testpositions (Long and big post).

Post by ardee »

Vinvin wrote:
ardee wrote:Please forgive my ignorance, but here's one more from that list that I cannot get, even with help from programs:

[d]2b1r3/r2ppN2/8/1p1p1k2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1

White can reportedly draw via 1. Nd6+, but after 1. ... exd6 I don't see the draw. (Don't see a way to keep checking or to block Black's other Rook in or to promote a pawn, even beginning with 2. a3).

Got more analysis for this one? For some of the other tactical ones that strong programs like Rybka cannot get?
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Pos"]
[Black "?"]
[Result "1/2-1/2"]
[SetUp "1"]
[FEN "2b1r3/r2ppN2/8/1p1p1k2/pP1P4/2P3R1/PP3PP1/2K5 w - - 0 1"]
[PlyCount "31"]

{Building a fortress} 1. Nd6+ $1 exd6 2. Rf3+ Kg5 3. Rg3+ Kf6 4. Rf3+ Ke7 5.
Re3+ Kd8 6. Rxe8+ Kxe8 7. a3 Ra8 8. Kd2 Bb7 9. Ke2 Kf7 10. Kf1 Rh8 11. Kg1 Kf6
12. f3 Kf5 13. g3 Re8 14. Kf2 Re7 15. Kf1 Rh7 16. Kg2 1/2-1/2
Amazing! First, I never thought to exchange rooks. Second, I've seen a number of fortresses over the years, but none like this one. Great puzzle -- thanks for the solution!!
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Vinvin
Posts: 5300
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: 83 nice Testpositions (Long and big post).

Post by Vinvin »

Roy Eassa wrote: ...
Great puzzle -- thanks for the solution!!
No problem, Roy, you're welcome :wink:
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Vinvin
Posts: 5300
Joined: Thu Mar 09, 2006 9:40 am
Full name: Vincent Lejeune

Re: 83 nice Testpositions (Long and big post).

Post by Vinvin »

Roy Eassa wrote: ...
Amazing! First, I never thought to exchange rooks. Second, I've seen a number of fortresses over the years, but none like this one. Great puzzle -- thanks for the solution!!
BTW, you can find some lines in the compilation I made last year : http://home.scarlet.be/vincentlejeune/h ... -beta3.pgn
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ardee

Re: 83 nice Testpositions (Long and big post).

Post by ardee »

Vinvin wrote:
Roy Eassa wrote: ...
Amazing! First, I never thought to exchange rooks. Second, I've seen a number of fortresses over the years, but none like this one. Great puzzle -- thanks for the solution!!
BTW, you can find some lines in the compilation I made last year : http://home.scarlet.be/vincentlejeune/h ... -beta3.pgn
Thank you! I've been away from this forum, and from computer chess, for quite awhile.

I know that Rybka has become huge, but I've completely lost track of the progress of the other engines that were big a few years ago (and any other new ones besides Rybka). A brief summary by somebody would be cool.

But my favorite thing of all is tactical problems that I can understand but that are too hard or deep for most programs.

I really appreciate the help you & Uri have provided. :D
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ardee

Re: 83 nice Testpositions (Long and big post).

Post by ardee »

On this puzzle:

Play Kh1!! that wins. Other moves draw.
[d]8/7p/5p2/6k1/8/6P1/5PPK/8 w - - 0 1

Could somebody explain how/why this move wins (and no other move does). It's too deep for me to see, even with computer help.

TIA!
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