It is currently Thu Oct 31, 2024 3:57 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 8 posts ] 
Author Message
Offline
 Post subject: 501 tesuji problems #92, what is the profit?
Post #1 Posted: Fri Aug 23, 2013 3:16 am 
Lives in sente
User avatar

Posts: 801
Location: Amsterdam (NL)
Liked others: 353
Was liked: 107
Rank: KGS 7 kyu forever
GD Posts: 460
After my yesterday failure I'll try to be more modest by just asking a question.

Click Here To Show Diagram Code
[go]$$Bc find b's tesuji
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . . . . . .
$$ | . O . O . . O . .
$$ | . O O X X X O . .
$$ | . . X O O O X O .
$$ | . . X X . X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]

Problemstatement:
B's stones are confined to the bottom. How can he create some aji to help him break out into the open.

Click Here To Show Diagram Code
[go]$$Bcm1 nuki
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . a 2 . . .
$$ | . O . O . . O . .
$$ | . O O X X X O b .
$$ | . . X O O O X O .
$$ | . . X X 1 X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]

If white plays :w2:, B can aim at a which gives W bad aji in combination with the cutting point b.

Click Here To Show Diagram Code
[go]$$Bcm1 failure
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . . 2 4 . .
$$ | . O . O . 1 O . .
$$ | . O O X X X O . .
$$ | . . X O O O X O .
$$ | . . X X 3 X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]


Question:
I dont see b's profit clearly in this exchange. If w wants to avoid the aji he can play his 2 one point lower.
Is B forcing W to make a choice?

_________________
I think I am so I think I am.

Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #2 Posted: Fri Aug 23, 2013 4:16 am 
Lives in gote

Posts: 408
Location: Poland, Gliwice
Liked others: 127
Was liked: 94
Rank: EGF 3kyu
Universal go server handle: tommyray (1d/2d)
If we agree that aji is some kind of potential, that if you take 3 stones white has dilemma: defend in gote, or take sente but leaving aji behind may be dangerous.
So yes, taking stones these stones which creates aji is a correct solution.

_________________
Tsumego/Tesuji apps for iPad, iPhone & Android devices:http://www.lifein19x19.com/forum/viewtopic.php?f=18&t=7511


This post by lobotommy was liked by: cyclops
Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #3 Posted: Fri Aug 23, 2013 5:04 am 
Lives in sente
User avatar

Posts: 801
Location: Amsterdam (NL)
Liked others: 353
Was liked: 107
Rank: KGS 7 kyu forever
GD Posts: 460
lobotommy wrote:
... that if you take 3 stones white has dilemma: defend in gote, or take sente but leaving aji behind ...

thx for your answer. But I fail to see that :w2: in my first hidden diagram is W's sente. It seems gote so W will prefer to play solid to prevent B's profit. BTW, I don't doubt the correctness of the book's solution but I cant see b's profit from it.

_________________
I think I am so I think I am.

Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #4 Posted: Fri Aug 23, 2013 5:42 am 
Gosei
User avatar

Posts: 2011
Location: Groningen, NL
Liked others: 202
Was liked: 1087
Rank: Dutch 4D
GD Posts: 645
Universal go server handle: herminator
That's just an incredibly subtle position, and the profit is very vague. In plenty of positions, white would tenuki rather than play :w2:.

The solution is really only a solution because the problem statement specifies that it is considered valuable for black to create aji here.

As to the alternative:

Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . 4 a . . .
$$ | . O . O 3 2 O . .
$$ | . O O X X X O b .
$$ | . . X . . . X O .
$$ | . . X X 1 X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]


Now there is still aji with the cutting points a and b.

THe book's solution:

Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . c a d . . .
$$ | . . O . 3 2 . . .
$$ | . O . O b . O . .
$$ | . O O X X X O . .
$$ | . . X . . . X O .
$$ | . . X X X X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]


White has some more flexibility. Now he can choose a or b, and if he chooses a and black plays b, he then has options c and d.


This post by HermanHiddema was liked by 3 people: cyclops, ez4u, Phoenix
Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #5 Posted: Fri Aug 23, 2013 3:25 pm 
Lives in sente
User avatar

Posts: 801
Location: Amsterdam (NL)
Liked others: 353
Was liked: 107
Rank: KGS 7 kyu forever
GD Posts: 460
thx, herman. I gradually believe the problem is too difficult for me. No problem accepting so. I hope to live in Groningen some time soon.

_________________
I think I am so I think I am.

Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #6 Posted: Fri Aug 23, 2013 4:37 pm 
Oza
User avatar

Posts: 2408
Location: Tokyo, Japan
Liked others: 2346
Was liked: 1332
Rank: Jp 6 dan
KGS: ez4u
cyclops wrote:
thx, herman. I gradually believe the problem is too difficult for me. No problem accepting so...

I am not sure that is the right lesson to take away. IMHO, this problem rather stretches the boundary of what we usually mean by "tesuji". For the record...

The shape arises from a rare variation of the large avalanche when Black in the first game below (White in the original problem) turns outward with :b1:. The earliest appearance in GoGoD is this game. Kitani indeed captured with :w10:
Click Here To Show Diagram Code
[go]$$Bc Kitani Minoru (White) - Fujisawa Kuranosuke; Oteai 1937-11-03,04
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . O . . . . |
$$ | . . . , . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 5 . . |
$$ | . . . . . . . . . . . . . . 3 X 2 6 . |
$$ | . . . . . . . . . . . . . . . O X 8 . |
$$ | . . . . . . . . . . . . . . . O X 0 . |
$$ | . . X , . . . . . , . . . . 9 O X 4 . |
$$ | . . . . . . . . . . . . . 7 O X O O . |
$$ | . . . . . . . . . . . . . . 1 X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Overall there are ten games in GoGoD with the problem shape. Four times the player captured the three stones (the "tesuji"). The other six times they played elsewhere. For example...
Click Here To Show Diagram Code
[go]$$Wc Fujisawa Hideyuki (White) - Takemiya Masaki; 11th Hayago Championship 1978-10-07
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O 1 . . . . . . . . . . . . . . |
$$ | . X X O X 9 . . . . . . 0 . . . . . . |
$$ | . 4 O X 7 . . . . , . . . . . X . . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . 8 O X . . . . . . . . . . . . . . . |
$$ | . 6 2 O 3 . . . . . . . . . . . . . . |
$$ | . . 5 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


As a quick sanity check, I flipped fifty moves ahead in the six games with a tenuki. Neither player returned to settle the gap in this shape within fifty moves in any of the six games. As Herman wrote, the aji here is indeed very subtle.

_________________
Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21


This post by ez4u was liked by 2 people: Bill Spight, cyclops
Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #7 Posted: Fri Aug 23, 2013 4:59 pm 
Lives in gote
User avatar

Posts: 447
Liked others: 137
Was liked: 68
Rank: kgs 5kyu
KGS: Unusedname
Click Here To Show Diagram Code
[go]$$Bcm1 failure
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . . 2 4 . .
$$ | . O . O . 1 O . .
$$ | . O O X X X O . .
$$ | . . X O O O X O .
$$ | . . X X 3 X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]


Well if you change the move order you can see that pushing at 1 is aji keshi.
in the second diagram the exchange 3 for 4 is terrible.

Click Here To Show Diagram Code
[go]$$Bcm1 nuki
$$ | . . . . . . . . .
$$ | . . , . . . . , .
$$ | . . . . . . . . .
$$ | . . O . a 2 4 . .
$$ | . O . O . 3 O . .
$$ | . O O X X X O b .
$$ | . . X O O O X O .
$$ | . . X X 1 X X . .
$$ | . . . . . . . . .
$$ +------------------[/go]


This post by Unusedname was liked by: gasana
Top
 Profile  
 
Offline
 Post subject: Re: 501 tesuji problems #92, what is the profit?
Post #8 Posted: Sat Aug 24, 2013 11:03 am 
Gosei
User avatar

Posts: 2011
Location: Groningen, NL
Liked others: 202
Was liked: 1087
Rank: Dutch 4D
GD Posts: 645
Universal go server handle: herminator
cyclops wrote:
thx, herman. I gradually believe the problem is too difficult for me. No problem accepting so. I hope to live in Groningen some time soon.


More players in Groningen is always a good thing! :D

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group