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Subject: Re: 5 difficult positions?

Author: Eelco de Groot

Date: 04:50:21 02/10/02

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On February 10, 2002 at 06:24:24, Eelco de Groot wrote:

>On February 10, 2002 at 05:34:23, Eelco de Groot wrote:
>
>>On February 09, 2002 at 23:09:07, Albert Silver wrote:
>>
>>>On February 09, 2002 at 19:55:58, Andrew Williams wrote:
>>>
>>>>Hi Ed,
>>>>
>>>>PostModernist says:
>>>>
>>>>EPD TEST SET: rebelhard.epd - 360 seconds per position
>>>>
>>>>ID rebelhard.epd.0001 - CORRECT in     6.05 seconds. nodes: 354557
>>>
>>>Could you post the analysis and a few lines beyond?
>>>
>>>                                   Albert
>>>
>>>>ID rebelhard.epd.0002 - WRONG. nodes: 35362560 (Nxh6)
>>>>ID rebelhard.epd.0003 - WRONG. nodes: 53597184 (Kd2)
>>>>ID rebelhard.epd.0004 - WRONG. nodes: 76704256 (Rf3)
>>>>ID rebelhard.epd.0005 - CORRECT in   273.02 seconds. nodes: 45357242
>>>>
>>>>RESULT: 2 Correct (5 positions @ 360 seconds).
>>>>
>>>>NODES per second 163993
>>>>
>>>>
>>>>This is on an Athlon 1200.
>>>>
>>>>Andrew
>>
>>
>>Me too! I would like to know what Troitzky's intended line was in his study. I
>>couldn't find the study on the Net, so far.
>>
>>Trying Q5T it won't play Rf7:
>>
>>[d]k2N2K1/8/8/8/5R2/3n4/3p4/8 w - - bm Rf7 (Troitzky);
>>
>>Game begin
>>
>>00:00  05.01  -3.22  1.Rf1
>>00:00  07.01  -3.71  1.Rf1
>>00:01  08.00  -4.01  1.Ra4+ Kb8 2.Ra1 Nc1 3.Rb1+ Kc8 4.Nf7 d1=Q
>>00:01  08.01  -3.79  1.Rf1 Ne1 2.Nf7 d1=Q 3.Rg1 dxe2 4.Rg7
>>00:02  09.00  -3.97  1.Rf1 Ne1 2.Ne6 d1=Q 3.Rf8+ Kb7 4.Rf7+
>>00:05  10.00  -4.06  1.Rf1 Ne1 2.Ne6 d1=Q 3.Rf8+ Kb7 4.Rf7+
>>00:16  11.00  -4.40  1.Rf1 Ne1 2.Nc6 d1=Q 3.Rf8+ Kb7 4.Nd8
>>01:35  12.00  -4.39  1.Rf1 Ne1 2.Nc6 d1=Q 3.Rf8+ Kb7 4.Nd8+
>>04:05  13.00  -4.59  1.Rf1 Ne1 2.Nc6 d1=Q 3.Rf8+ Kb7 4.Nd8+
>>22:10  14.00  -4.59  1.Rf1 Ne1 2.Nf7 d1=Q 3.Rg1 Ka7 4.Rg7
>>13:11  15.00  -4.76  1.Rf1 Ne1 2.Nf7 d1=Q 3.Rg1 dxb3 4.Rg7
>>
>>And after 1.Rf7:
>>
>>Rebel Engine for ECTool. (c) Ed Schröder
>>
>>Engine version   :  REBEL CENTURY 2
>>Rebel personality :  "Personality Q5T"
>>Opening book file :  RebelC.mvs
>>Hash table size  :  4 MB
>>Analysis mode   :  Analyzing next move
>>Refresh interval : 500 ms
>>
>>Last Move : 1.Rf7 (Black to play)
>>
>>00:00  05.00  4.54  1..d1=Q 2.Re7 Nc5 3.Ne6 dxg4+ 4.Ng7
>>00:01  08.00  5.09  1..d1=Q 2.Re7 Nc5 3.Ne6 dxd5 4.Re8+ Kb7
>>00:02  09.00  5.47  1..d1=Q 2.Re7 dxg4+ 3.Rg7 gxc8 4.Kh7 Nf4
>>00:04  10.00  5.90  1..d1=Q 2.Ne6 dxg4+ 3.Ng7 Ne5 4.Rf5 g3
>>00:06  11.00  5.91  1..d1=Q 2.Ne6 Ne5 3.Re7 dxg4+ 4.Ng7 gxg5
>>01:16  12.00  6.55  1..d1=Q 2.Rf8 dxg4+ 3.Kh7 gxh4+ 4.Kg8 hxg5+
>>03:43  13.00  6.15  1..d1=Q 2.Rf8 dxg1=Q+ 3.Kh7 gxh2+ 4.Kg7 hxe5+
>>06:14  14.00  6.13  1..d1=Q 2.Rf8 dxg4+ 3.Kh7 gxh4+ 4.Kg7 hxg5+
>>25:49  15.00  6.59  1..d1=Q 2.Rf8 dxg4+ 3.Kh7 gxh4+ 4.Kg8 hxg5+
>>07:27  16.00  6.59  1..d1=Q 2.Rf8 dxg4+ 3.Kh7 gxh4+ 4.Kg8 hxg5+
>>
>>Iteration 17 looks to be a fail-low but that could take quite a while. Celeron
>>500 MHz, clocking 8 hours so far on a reply to 1.Rf7.
>
>After 1.Rf7 d1=Q 2.Nc6 I get the following. No more phantom pieces taken by the
>queen, maybe that was just a glitch from retrieving lines from hash, but still 7
>pawns difference from seeing it as a draw:
>
>
>Last Move : 2.Nc6 (Black to play)
>
>00:04  07.00  9.30  2.Ne5 Kg7 3.Qd4 Ne6 4.Qg4 Kf6 5.Nc6 Ng5 6.Kb8
>00:00  03.00  6.59  2..Qg4+ 3.Rg7 Qc8+ 4.Kh7 Qxc6 5.Kh8 Qh6
>00:00  05.00  6.96  2..Qg4+ 3.Kh7 Qe4+ 4.Kg7+ Qxc6 5.Rf8+ Kb7 6.Rf7 Kc8+ 7.Kg8
>Qe6
>00:01  06.00  6.91  2..Qg4+ 3.Kf8 Qc8+ 4.Kg7 Qxc6 5.Rf8+ Kb7 6.Rf7 Kc8 7.Rf8+
>00:02  07.00  6.97  2..Qg4+ 3.Kf8 Qc8+ 4.Kg7 Qxc6+ 5.Rf8
>00:04  08.00  6.92  2..Qg4+ 3.Kf8 Qc8+ 4.Kg7 Qxc6+
>00:14  09.00  7.05  2..Qg4+ 3.Kf8 Qc8+
>00:48  10.00  7.05  2..Qg4+ 3.Kf8 Qc8+ 4.Kg7 Qxc6+ 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8
>Kd7 8.Rf7
>04:07  11.00  6.88  2..Qg4+ 3.Kf8 Qc8+ 4.Kg7 Qxc6+ 5.Rf8+ Kb7 6.Rg8 Qe4 7.Kf7
>Kc6 8.Re8
>09:55  12.00  7.02  2..Qg4+ 3.Kf8
>
>Is this ending Queen vs. Rook really a draw? Then I think RC4 will see that,
>even without Nalimov tablebases and the fact that RC2(Q5T) couldn't see it isn't
>really relevant anymore of course. So I'm interested what RC4 would make of it!
>
> Eelco

As Uri pointed out it is Queen and Knight against Rook. Thanks Uri, I totally
forgot that noble animal there on d3!. After entering a few more moves now in
regular Rebel Century 2 (without tablebases of course) after about 1 minute
Century 2 sees a draw around the corner:


[Event ""]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result ""]
[FEN "k2N2K1/8/8/8/5R2/3n4/3p4/8 w - - bm Rf7 (Troitzky);"]

1.Rf7 d1=Q 2.Nc6 Qg4+ 3.Kf8 Qc8+ 4.Kg7  *

Last Move : 4.Kg7 (Black to play)

00:00  06.00  7.68  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Kg8 Qd5
00:00  07.00  7.59  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8 Ke7 12.Rf7+ Kd8 13.Rf8
00:00  08.00  6.74  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8 Kc7 12.Rf7+ Kd8 13.Rf8 Kc7 14.Rf7+
00:07  09.00  7.62  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8
00:08  10.00  6.74  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8
00:16  11.00  7.60  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8 Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8
00:27  12.00  6.69  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd8 11.Rf8
01:14  13.00  0.00  4..Qxc6 5.Rf8+ Kb7 6.Rf7+ Kc8 7.Rf8+ Kd7 8.Rf7+ Ke8 9.Rf8+
Ke7 10.Rf7+ Kd6 11.Rf6 Kd5 12.Rxc6




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