Difficult studies

peter · Post by **peter** » Fri Mar 10, 2017 10:47 pm

Nordlandia wrote:
peter wrote:Or am I wrong and have seen that anywhere else but form you, Jon?
It is certainly possible that i have posted this study earlier, even though i didn't manage to find it in Complex Puzzle (last few pages).

I can't remember last time i cooked work from Oleg Pervakov.

Kasparov said he admired compositions from him.

So do I, Jon, yet I still think we had this here before, but I can be wrong as well as for the outcome after 4...Be5.
Yet 4...Bf6 as in author's solution given is a rather simplifying shortcut, if it came up in a game, I'd give it a ?, and in a study there should be a mention and a side- line at least.

Not sure, if this interactive line is correct, anyhow it worked for a full point here too:

4r3/kp1p2p1/p5R1/K7/n7/1B4B1/1b6/5R2 b - - 0 1

1... Nb6 2. Rf3 Rf8 3. Bb8+ Rxb8 4. Rxb6 Be5 5. Rg6 Rc8 6. Rf7 Rc6 7. Rxc6 dxc6
8. Be6 Bc3+ 9. Ka4 Kb8 10. Rf8+ Kc7 11. Rc8+ Kb6 12. Re8 Kc7 13. Bg4 g5 14.
Rc8+ Kb6 15. Rg8 Kc7 16. Rxg5 Bd2 17. Rg7+ Kb8 18. Bf5 Be3 19. Rf7 Bf4 20. Kb4
Be3 21. Kc3 Bc5 22. Bd3 Bd6 23. Rh7 Bc5 24. Kb3 Bd4 25. Kc4 Be5 26. Be4 Bb2 27.
Bg6 Be5 28. Kc5 Bf4 29. Kd4 Kc8 30. Bf5+ Kb8 31. Ke4 Bg3 32. Bg6 Ka7 33. Be8
Kb8 34. Kf5 Bf2 35. Bg6 Be1 36. Ke6 Bg3 37. Bc2 Bf4 38. Be4 Kc8 39. Bg6 Bd2 40.
Bc2 Be3 41. Bg6 Bc5 42. Kf7 Kd7 43. Kf6+ Kc8 44. Bf5+ Kb8 45. Kf7 a5 46. Ke8 a4
47. Kd7 a3 48. Be6 Bb4 49. Rh3 Bc5 50. Rh8+ Ka7 51. Kc7 Bd4 52. Rh3 Be5+ 53.
Kc8 b5 54. Rxa3+ Kb6 55. Kd7 Bd4 56. Bf7 Bb2 57. Rg3 Kc5 58. Rg6 Ba3 59. Ba2
Bb2 60. Rxc6+ Kd4 61. Rb6 Bc1 62. Rxb5 Ba3 63. Rd5+ Ke4 64. Ke6 Bb2 65. Rd1 Bc3
66. Bd5+ Kf4 67. Rd3 Be1 68. Rf3+ Kg4 69. Rf5 Bd2 70. Ke5 Be1 71. Be6 Bg3+ 72.
Ke4 Bh4 73. Bd7 Kg3 74. Rf3+ Kg2 75. Bh3+ Kh2 76. Rd3 Bg5 77. Bf1 Kg1 78. Kf3
Bh4 79. Bg2 Be1 80. Rb3 Bd2 81. Rb1+ Be1 82. Rxe1+ Kh2 83. Rh1#

peter · Post by **peter** » Sat Mar 11, 2017 12:05 am

After Backward of the line above to the position after
4r3/kp1p2p1/p5R1/K7/n7/1B4B1/1b6/5R2 b - - 0 1
1... Nb6 2. Rf3 Rf8 3. Bb8+ Rxb8 4. Rxb6 Be5
I get this output

1r6/kp1p2p1/pR6/K3b3/8/1B3R2/8/8 w - - 0 1

Analysis by pedantFishW_2017-03-09_popcnt:

5.Rg6 Bf6 6.Rg2 Rh8 7.Kb4 d6 8.Rd3 Rh4+ 9.Ka3 Bd4 10.Be6 Re4 11.Kb3 Bf6 12.Bd5 Re7 13.Rc2 Kb8 14.Ka4 Re1 15.Kb4 Rb1+ 16.Rb3 Ra1 17.Be6 Rd1 18.Rc8+ Ka7 19.Bg4 Re1 20.Bf3 Re7 21.Bd5 Bd4 22.Rf3 Bc5+ 23.Kc3 Re5 24.Rd3 Re7 25.Rg3 g5 26.Rxg5 Re3+ 27.Kd2 Re7 28.Rg4 Be3+ 29.Kc3 Bc5 30.Rg3 Bf2 31.Rg5 Kb6 32.Kb3 Re5 33.Rxe5 dxe5
+- (2.89) Depth: 38/78 00:05:46 9954MN, tb=18914919

At the end of this line the won 7some position is almost reached.

Guess I stand corrected about White's possibility to build a fortress with 4 Pawns against the Rook

Nordlandia · Post by **Nordlandia** » Sat Mar 11, 2017 1:03 pm

Here is another mind-boggling study

[d]4k3/7p/6Np/p2n4/3Q4/P5pP/P5K1/1q6 w - - 0 0

My analysis so far

Code: Select all

&#91;Event "?"&#93;
&#91;Site "?"&#93;
&#91;Date "????.??.??"&#93;
&#91;Round "?"&#93;
&#91;White "New game"&#93;
&#91;Black "?"&#93;
&#91;Result "*"&#93;
&#91;SetUp "1"&#93;
&#91;FEN "4k3/7p/6Np/p2n4/3Q4/P5pP/P5K1/1q6 w - - 0 0"&#93;
&#91;PlyCount "13"&#93;

1. Qe5+ Kf7 2. Nh8+ Kf8 3. Qxd5 Qc2+ &#40;3... Qb2+ $6 &#123;Weak move&#125;) 4. Kxg3 Qc7+ 5.
Kf3 Kg7 6. Qd4+ Kg8 7. a4 *

http://www.viewchess.com/cbreader/2017/ ... 57968.html

Nordlandia · Post by **Nordlandia** » Sat Mar 11, 2017 2:06 pm

Possible cook detected

Winning 8-Man EGTB position.

[d]qn6/bP2B3/1P6/3K1n2/8/4p3/Q1P2k1p/8 w - - 0 0

[d]8/8/2n5/5n1k/2KBq3/2P5/8/6Q1 w - - 0 9

[pgn][Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "New game"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "qn6/bP2B3/1P6/3K1n2/8/4p3/Q1P2k1p/8 w - - 0 0"]
[PlyCount "18"]

1. c3+ e2 2. Bc5+ Kg3 3. bxa8=Q h1=Q+ 4. Kc4 Qxa8 5. Qxe2 Bxb6 6. Qf2+ Kg4 7.
Qg1+ Kh5 8. Bxb6 Qe4+ 9. Bd4 Nc6 *

[/pgn]

Code: Select all

&#91;Event "?"&#93;
&#91;Site "?"&#93;
&#91;Date "????.??.??"&#93;
&#91;Round "?"&#93;
&#91;White "New game"&#93;
&#91;Black "?"&#93;
&#91;Result "*"&#93;
&#91;SetUp "1"&#93;
&#91;FEN "qn6/bP2B3/1P6/3K1n2/8/4p3/Q1P2k1p/8 w - - 0 0"&#93;
&#91;PlyCount "18"&#93;

1. c3+ e2 2. Bc5+ Kg3 3. bxa8=Q h1=Q+ 4. Kc4 Qxa8 5. Qxe2 Bxb6 6. Qf2+ Kg4 7.
Qg1+ Kh5 8. Bxb6 Qe4+ 9. Bd4 Nc6 *

------

I have gone trough EG released from 2010-to 2015 the last month.

I have posted those who seemed interesting, i.e difficult for current engines.

peter · Post by **peter** » Sat Mar 11, 2017 10:44 pm

Nordlandia wrote:Possible cook detected

Winning 8-Man EGTB position.

You doubt it to be draw?

[d]qn6/bP2B3/1P6/3K1n2/8/4p3/Q1P2k1p/8 w - - 0 1

Analysis by Stockfish MateFinder 64:

1.c3+ e2 2.Bc5+ Kg3 3.bxa8Q h1Q+ 4.Kc4 Qxa8 5.Qxe2 Bxb6 6.Qf2+ Kg4 7.Qg1+ Kh5 8.Bxb6 Qe4+ 9.Bd4 Nc6 10.Qh2+ Kg5 11.Qg1+ Kh6 12.Qh2+ Kg6 13.Kc5 Nce7 14.Qe5 Qc6+ 15.Kb4 Qb7+ 16.Ka3 Qa8+ 17.Kb2 Qg2+ 18.Ka3 Qf3 19.Qh8 Qd3 20.Kb2 Qd2+ 21.Kb3 Qd1+ 22.Kb2 Qe2+ 23.Kc1 Qa6 24.Kb2 Kg5 25.Qf6+ Qxf6 26.Bxf6+
= (0.00) Depth: 41/54 00:01:13 1578MN, tb=54515514

Nordlandia · Post by **Nordlandia** » Mon Mar 27, 2017 7:46 am

[d]q1b5/1p6/5P2/4N3/1B1p4/p5k1/K5N1/3B4 w - - 0 0

[d]8/1p1B4/5q2/4N3/1B1p3N/p5k1/K7/8 b - - 0 3

Candidate moves ->

4...Qf2+

4...Qf1+

My conslusion -> based on stockfish evaluation of ~ 1.50 this endgame is probably won for white.

Nordlandia · Post by **Nordlandia** » Tue May 09, 2017 10:44 am

Stockfish and H5 did not find the solution.

[d]1K6/1pp3k1/1R5b/7p/1B4p1/2Pp4/7P/8 w - - 0 0

peter · Post by **peter** » Tue May 09, 2017 1:25 pm

Hi Jon!

Nordlandia wrote:Stockfish and H5 did not find the solution.

[d]1K6/1pp3k1/1R5b/7p/1B4p1/2Pp4/7P/8 w - - 0 0

McBrain 2.3 didn't neither within 5 minutes at default setting and 22threads, but with Tactical set to 3 instead of 0:

1K6/1pp3k1/1R5b/7p/1B4p1/2Pp4/7P/8 w - - 0 1

Analysis by McBrain 2017 2.3 64 POPCNT:

1.Rb5 d2 2.Rd5 Bf4 3.Kxb7 Kg6 4.Kc6
+/- (1.33) Depth: 7/9 00:00:04 85kN
...
1.Rxb7 d2 2.Rxc7+ Kf6 3.Rd7 h4 4.c4 g3 5.hxg3 hxg3 6.Bxd2 g2 7.Bc3+ Ke6 8.Rd1 Be3 9.Kc7 g1Q 10.Rxg1 Bxg1 11.Kc6 Be3 12.Bb4 Ke5 13.Bc5 Bg5 14.Bd6+ Ke6 15.Bc7 Bh6 16.Bb6 Bg7 17.Bg1 Ke7 18.c5 Bc3 19.Be3 Kd8
+/- (0.85) Depth: 16/41 00:00:04 13997kN
...
1.Rxb7 Kf6 2.Ba5 h4 3.Bxc7 Kf5 4.c4 Ke4 5.Bd6 Bc1 6.Rb5 Be3 7.c5 d2 8.Rb1 Kd5 9.Kc7 Bxc5 10.Bf4 Bb4 11.Rg1 Ke4 12.Bxd2 Bxd2 13.Rxg4+ Bf4+ 14.Kb7 h3 15.Rh4 Kf3 16.Rxh3+ Kg2 17.Rh7 Bxh2
= (0.28) Depth: 22/47 00:00:15 343MN
1.Bf8+ Kf7 2.Rxh6 d2 3.Rh7+ Ke8 4.Re7+ Kd8 5.Bh6 d1Q 6.Bg5 Qd6 7.Re6+ Kd7 8.Rxd6+ cxd6 9.Kxb7 d5 10.Kb6 d4 11.cxd4 Kd6 12.Kb5 Kd5 13.Bf6 h4 14.Bxh4 Kxd4 15.Kc6 Kc4 16.Bg5 Kd3 17.Kd5
+- (2.51) Depth: 23/47 00:00:15 347MN
...
1.Bf8+ Kf7 2.Rxh6 d2 3.Rh7+ Ke8 4.Re7+ Kd8 5.Bh6 Kxe7 6.Bxd2 Ke6 7.Kxc7 h4 8.Be1 h3 9.Kxb7 Kd5 10.Kb6 Kc4 11.Kc6 g3 12.Bxg3 Kxc3 13.Kd5 Kb4 14.Ke5 Kc5 15.Kf5 Kd5 16.Bf4 Kc4 17.Kg4 Kd5
+- (3.11) Depth: 24/47 00:00:16 396MN
...
1.Bf8+ Kg8 2.Rg6+ Kf7 3.Rxh6 d2 4.Rh7+ Ke8 5.Re7+ Kd8 6.Bh6 d1Q 7.Bg5 Qd6 8.Re6+ Kd7 9.Rxd6+ cxd6 10.Kxb7 d5 11.Bf4 Ke6 12.Kc6 Kf5 13.Bg3 Ke4 14.Kc5 Kd3 15.Kxd5 Kxc3 16.Ke5 Kd3 17.Kf4 Kd4 18.Kg5 Ke4 19.Kxh5 Kf5 20.Kh4 Kg6 21.Kxg4 Kg7 22.h4 Kg6 23.h5+ Kf6 24.Kf4 Kf7
+- (4.41) Depth: 30/78 00:01:07 2086MN

And after some Forward- Backward with asmFish:

1K6/1pp3k1/1R5b/7p/1B4p1/2Pp4/7P/8 w - - 0 1

Analysis by pedantFishW_2017-05-02_popcnt:

1.Bf8+ Kg8 2.Rg6+ Kf7 3.Rxh6 d2 4.Rh7+ Ke8 5.Re7+ Kd8 6.Bh6 d1Q 7.Bg5 Qd6 8.Re6+ Kd7 9.Rxd6+ cxd6 10.Kxb7 d5 11.Bf4 Ke6 12.Bg3 d4 13.cxd4 Kd5 14.Kc7 Kxd4 15.Kd6 Kc4 16.Ke6 Kc5 17.Kf6 Kd4 18.Kg5 Ke4 19.Kxh5 Kf5 20.Bc7 g3 21.Bxg3 Ke4 22.Kg4 Kd5 23.Kf5 Kc6 24.h4 Kd7 25.h5 Ke7 26.h6 Kf7 27.Bf4 Kf8 28.Kf6 Ke8 29.Ke6 Kf8 30.Bg5 Kg8 31.Kf6 Kh7 32.Kf7 Kh8 33.Kg6 Kg8 34.h7+ Kh8 35.Bf6#
+- (#35) Depth: 61/70 00:00:27 1488MN

Nordlandia · Post by **Nordlandia** » Wed May 10, 2017 3:27 pm

EG No. 208 april 2017 supplement, page 151.

White wins!

[d]3q4/5kpp/pr1P3Q/p3p3/b1p5/6P1/3PR3/5BK1 w - - 0 0

Nordlandia · Post by **Nordlandia** » Wed May 10, 2017 4:01 pm

White wins. Stockfish found fortress with no progression.

[d]3q2k1/1pr3pp/5P2/6pP/2p1B2r/4QP1P/R5bP/6K1 w - - 0 0

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