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Posted by ganstaman
chessbase.net

5/04/2008
08:11:43

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Subject: Puzzle 283

Message:
Ok, the puzzle on the homepage at the time of me writing this (search for puzzle number 283 here: gameknot.com )



White to move, mate in 4. I won't spoil the solution given, as it is brilliant seeming to me.

But how can black spoil white's plan of Qh4-(h or e)7-b7#? I can see black delaying the journey by 1 move, so it would be mate in 4. What did I miss, if anything?

Posted by heinzkat
chessbase.net

5/04/2008
08:21:53

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I think the answer is

Message:
1. Qh4 Rh1!

Posted by sf115
chessbase.net

5/04/2008
08:35:09

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Message:
If 1. Qh4 Rh1 white either:

2. Qxh1 a1=Q 3. Qh7 Qxa6+ 4. bxa6 b1=Q 5. Qb7++ which is a move slower than the actual solution.

OR

2. continue with the original plan with 2. Qe7 Rh8+ 3. Nd8 Rh7 (3...Rxd8 also slows down whites mate) 4. Qb7+ Rxb7 5. axb7++ which is also in 5 moves.

So there is only a mate in 5, which is slower than the actual solution
———
Favorites Begin Quickly at U.S. Chess Championship — Hikaru Nakamura, Gata Kamsky and Alexander Onischuk, the top three seeds, all won their first games Friday at the United States Chess Championship in St. Louis. Five other chess players also won as the tournament got off to a fast and exciting start. The chess championship is being held at the Chess Club and Scholastic Center of Saint Louis and has a prize fund of $173,000. It has an unusual format this year. The first seven rounds will be a regular Swiss system in which players with the same number of points are paired. After seven rounds, the top four scorers will be separated from the rest of the tournament and play a round-robin amongst themselves, with the winner becoming chess ...
Posted by ganstaman
chessbase.net

5/04/2008
09:50:31

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Message:
Ah, that seems to do it. Thanks.
———
Day After Chess Championship, Victor and Vanquished Reflect on the Match — One day after their title match in Sofia, Bulgaria, ended, Viswanathan Anand, the once and still chess champion, and Veselin Topalov were tired, but proud. In separate telephone interviews on Wednesday, Anand and Topalov expressed satisfaction with their own efforts and said it was the most intense chess match they had ever played. “This is my first world chess championship match that has gone the distance,” said Anand. Referring to his earlier title matches against Vladimir Kramnik in 2008, which he won, and Garry Kasparov in 1995, which he lost, he continued, “With Kramnik it went like a dream, with Kasparov it went the opposite way.” Topalov said, “Every single game was ...
Posted by lighttotheright
chessbase.net

5/05/2008
03:53:48

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Message:
There is an alternate solution that is not accounted for by this puzzle. This kind of thing irritates me. It turns out that my first choice was in fact correct, but the puzzle said I made a mistake. Once you know the solution, it is easy to see that my alternate path works because mine is based on the same principles that are used in the given one.

It's still mate in four, but why are alternate solutions unaccounted for? I thought that problem was fixed long ago.
———
Anand Is World Chess Champion Again — Viswanathan Anand, the world chess champion, took advantage of a major error by Veselin Topalov to win the 12th and final game of their title match on Tuesday in Sofia, Bulgaria. The match had been tied at 5.5 points apiece. In addition to the title, Anand receives 1.2 million euros (about $1.5 million at current exchange rates). Topalov’s share of the prize fund is 800,000 euros, or about $1 million. Anand, an Indian grandmaster, became world chess champion by winning a tournament in Mexico City in 2007. He last defended the title in a match against Vladimir Kramnik, a Russian, in October 2008. Topalov, a Bulgarian, is a former world chess champion. He lost a bitter title match to ...
Posted by heinzkat
chessbase.net

5/05/2008
04:22:15

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That problem was fixed long ago

Message:
Lighttotheright, I think you're wrong here though - puzzle 283 has only one solution (for mate in four).
———
Title Match Is Tied With One Game to Go in Regulation — There is one more regulation game left in the World Chess Championship match in Sofia, Bulgaria. If neither Viswanathan Anand of India, the titleholder, or Veselin Topalov of Bulgaria, win on Tuesday, they will have to go to overtime. On Sunday, they drew Game 11. It was the seventh draw in the match, though, like some of the other draws, it was not without drama. Anand had White and opened with the English — the first time in the chess match he had done that. No doubt he switched openings to try to catch Topalov off-guard, but it did not work. The players followed well-known theory for 10 moves, and then Topalov deviated from earlier games, though it was a minor ...
Posted by lighttotheright
chessbase.net

5/05/2008
04:33:40

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Message:
The alternate 1. Nd8 works and is confirmed. It is mate in four just like the given solution.
———
Anand's missed opportunity — The chess World Championship is on a knife-edge. But Anand could have made a mark in this game. Anand and Topalov go into the 12th game of their chess match today with scores level. If drawn, tie-break rapid games will be played on Thursday. Topalov's declaration before the match that he would neither offer nor accept a draw has clearly had a liberating effect on both players, resulting in one of the most entertaining world chess championship finals we have seen in years. All the games have been long and hard-fought, so it's hardly surprising that tiredness is affecting play. Anand missed several chances to win in game 9, Topalov had a promising endgame in game 10 but ...
Posted by lighttotheright
chessbase.net

5/05/2008
04:38:41

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Message:
Heinzkat -- I'm not wrong. 1. Nd8 does work. The problem is that no computer can solve this particular problem from four moves out. The computer checking the solutions is wrong.

Once you input the solution, the computer suddenly sees the solution at 2 or 3 moves out depending upon the program that you use. This particular puzzle is an anti-computer one.


Posted by heinzkat
chessbase.net

5/05/2008
04:47:30

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Lighttotheright!

Message:
This is the interesting part of the puzzle, which is not covered in puzzle #283, since the puzzle application didn't support underpromotions of the opposite side back then. After 1. Nd8? [if I may boldly give it a ?] c2
2. Qc1 b1=B! Black is stalemated and there can be no mate in four.

After 1. Nb4 however, 1. ... c2 2. Qc1 b1=B 3. Nd3! exd3 4. Qh1, it IS mate in four :-)


Posted by chessnovice
chessbase.net

5/05/2008
04:48:12

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...

Message:
Sometimes puzzle makers don't have solutions entered entirely. Human error is prone to omissions. If you find an alternate solution, you're able to enter it. Nothing to necessarily get irritated about, I think.

Posted by heinzkat
chessbase.net

5/05/2008
04:55:26

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Also...

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Remember GameKnot does no checking of the puzzle at all - the puzzle application merely checks if all variations end in checkmate. If so, the puzzle is 'approved' 'correct' (twice '', ah well) an can be put up for others to solve. As you can see on the puzzle page, a lot of the puzzles still have some hiatuses then. If you think 1. Nd8 mates in four too, 'prove it'! You can do so by browsing to puzzle #283, hover over 'Options' in the right corner and click 'Alt. solution...'. This will give you the option to prove there is another way to play, that results in mate in at most the same number of moves as the original author. If all variations are correct, you can save the puzzle too, and the puzzle has been 'improved'.

Posted by lighttotheright
chessbase.net

5/05/2008
04:58:36

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Message:
1. Nd8 c2 2. Qc1 b1=B 3. Nd5 Qb2 (or any move) 4. Nc7#

It is forced checkmate. There is no stalemate with my solution. The alternate is confirmed, and not seen by computer at four moves out.

Posted by lighttotheright
chessbase.net

5/05/2008
05:00:17

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Message:
1. Nd8 c2 2. Qc1 b1=B 3. Nd5 Bb2 (or any move) 4. Nc7#

Sorry I made a slight error in copying the line. This is correct.

Posted by heinzkat
chessbase.net

5/05/2008
05:01:19

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2. ... b1=B!

Message:
Not 2. ... b1=Q. Please re-evaluate your assessments. :-)

(note that I hadn't noticed the b1=B solution either. A nice brilliancy by Ado Kraemer)

Posted by heinzkat
chessbase.net

5/05/2008
05:02:30

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Lighttotheright

Message:
3. ... Bb2 is not possible in the intended line! It's 2. ... b1=B, not 2. ... bxc1=B.

Posted by lighttotheright
chessbase.net

5/05/2008
05:03:18

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Message:
I did it again.

1. Nd8 c2 2. Qc1 b1=B 3. Ne6 Bb2 (or any move) 4. Nc7#

Those knight moves can get confusing.

I think this is correct now.


Posted by lighttotheright
chessbase.net

5/05/2008
05:06:00

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Message:
Heinskat look at the position. The key to the solutiion is the knight path. The Queen sac is to block any defence by black. The solution is very simple. 1. Nb4 and 1. Nd8 both work.

Posted by heinzkat
chessbase.net

5/05/2008
05:06:23

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Note that in your line...

Message:
3. ... Bb2 is illegal. In fact, after 3. Ne6, all Black's moves are illegal - it is stalemate!

Posted by heinzkat
chessbase.net

5/05/2008
05:09:59

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OK... with a diagram then...

Message:
After
1. Nd8 c2
2. Qc1 b1=B
3. Ne6
It is Black to move. Do you see any legal ones?



Interesting how Ado Kraemer can still keep us busy with his brilliant problems, 36 years after he died.

Posted by lighttotheright
chessbase.net

5/05/2008
05:14:36

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Message:
OK heinzkat. You threw me for a loop with b1. I was thinking about the c1 square. But even with b1=B, it is still checkmate in four. 1. Nd8 b1=b 2. Qxc3 and my solution still works.



Posted by heinzkat
chessbase.net

5/05/2008
05:21:11

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Well...

Message:
1. Nd8 c2
2. Qc1 b1=B is the line that makes mate in four impossible.

1. Nd8 b1=B like you give in this last post, perfectly mates in four - but there's a difference. Carefully check the notations right from the beginning of this thread, I think I haven't messed up any of them...

Posted by lighttotheright
chessbase.net

5/05/2008
05:21:54

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Message:
OK...It is still not stalemate. But it would be a mate in 5 instead. 1. Nd8 c2 2. Qc1 b1=B 3. Qxc2 and it is not stalemate. ...but it does take an extra turn to get the knight to c7.

Posted by lighttotheright
chessbase.net

5/05/2008
05:24:17

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Message:
Sorry for some of the copy mistakes. My copy function on my computer is not working. I have to reboot my whole computer to correct the problem.

Posted by heinzkat
chessbase.net

5/05/2008
05:24:20

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Exactly...

Message:
And therefore, 1. Nd8 is an incorrect try. Mate in five is possible in many ways - there is only one correct starting move to mate in four.

Posted by lighttotheright
chessbase.net

5/05/2008
05:58:50

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Message:
Well, it looked correct to me at the time. And my computer was not cooperating with me either!

Posted by chessnovice
chessbase.net

5/06/2008
13:55:37

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...

Message:
b1=B is pretty clever! Indeed, prolongs the Nd8 line by one move. I wouldn't worry about not considering that though, since I doubt that very many people really would.

Posted by bogg
chessbase.net

5/06/2008
15:13:15

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In case anyone else has the ...

Message:
same problem that I had. The reason that 2. ... b1=B doesn't cook 1.Nb4 and does cook 1. Nd4 and 1. Nd8 is because after 1.Nd4 White has 3. Nd3 ed: 4. Qh1++.

Took me a while to see the tree within the forest.
CTC

Posted by heinzkat
chessbase.net

5/07/2008
01:30:09

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chessnovice

Message:
Obviously the composer did consider it :)

bogg: indeed, see my post above too, 5/05/2008 04:47:30

Posted by chessnovice
chessbase.net

5/07/2008
01:44:28

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hienzkat

Message:
True. But if you can't trust the composer, who can you trust?

Posted by bogg
chessbase.net

5/07/2008
06:35:06

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heinzkat

Message:
Missed that post. Would have saved me some time had I noticed it.

CTC