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really unconditionally alive? (from "style of Iyama...")
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Author:  eyecatcher [ Mon Jul 25, 2016 3:00 am ]
Post subject:  really unconditionally alive? (from "style of Iyama...")
Hi everybody,

i`m reading "the style of Iyama Yuta" from Yuan Zhou at the moment. At game 2, move 103, he gives a variation for "living in the corner". He writes:

Quote:
"in this situation, Black could live unconditionally in this corner. The Variation "Living in the Corner" below shows the normal sequence."



So, while i`m still very weak at L&D i maybe just have a blind spot, but it think this is KO and not unconditionally alive? Or is it? :scratch:

And if it is... can you tell me how?

Click Here To Show Diagram Code
[go]$$B
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 2 . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 3 . O . . . . . , . . . . . , . . . |
$$ | . . 1 4 . . . . . . . . . . . . . . . |
$$ | . 7 . 5 6 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Author:  eyecatcher [ Mon Jul 25, 2016 3:17 am ]
Post subject:  Re: really unconditionally alive? (from "style of Iyama...")
here two (maybe not the best of course) variations... :)

Click Here To Show Diagram Code
[go]$$Wm1
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | 3 . X O . . . . . . . . . . . . . . . |
$$ | . X 2 X O . . . . . . . . . . . . . . |
$$ | . . . 1 . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | 7 6 . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | 4 . X O . . . . . . . . . . . . . . . |
$$ | . X 3 X O . . . . . . . . . . . . . . |
$$ | . 5 2 1 . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Author:  Krama [ Mon Jul 25, 2016 3:48 am ]
Post subject:  Re: really unconditionally alive? (from "style of Iyama...")
While white can limit black to 1 eye black could escape through series of ataris.
Author:  Uberdude [ Mon Jul 25, 2016 4:03 am ]
Post subject:  Re: really unconditionally alive? (from "style of Iyama...")
First point, I think you got 2 and 4 in wrong order for setup diagram:
Click Here To Show Diagram Code
[go]$$B
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 4 . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 3 . O . . . . . , . . . . . , . . . |
$$ | . . 1 2 . . . . . . . . . . . . . . . |
$$ | . 7 . 5 6 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Secondly, here is the basic idea of how to live without ko due to weaknesses in white's surrounding stones. (There are more sophisticated ways, e.g. play 4 at 6 first):
Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 9 . . . . . . . . . . . . . . . . |
$$ | . O 8 O . . . . . . . . . . . . . . . |
$$ | 7 6 0 . . . . . . . . . . . . . . . . |
$$ | 5 X . O . . . . . , . . . . . , . . . |
$$ | 3 . X O . . . . . . . . . . . . . . . |
$$ | 4 X 2 X O . . . . . . . . . . . . . . |
$$ | . . . 1 . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


(variation: if 9 ataris from other side then at a minimum white can live with 12 throw in as below, may even be able to extend from 10 depending on side position)

Click Here To Show Diagram Code
[go]$$Wm9 (7 connects at 4)
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 8 . . . . . . . . . . . . . . . . . |
$$ | 5 3 2 . . . . . . . . . . . . . . . . |
$$ | 4 O X O . . . . . . . . . . . . . . . |
$$ | O X 1 . . . . . . . . . . . . . . . . |
$$ | O X . O . . . . . , . . . . . , . . . |
$$ | O 6 X O . . . . . . . . . . . . . . . |
$$ | X X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm11
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 1 O 5 . . . . . . . . . . . . . . . |
$$ | . O X O 4 . . . . . . . . . . . . . . |
$$ | O X X 2 3 7 . . . . . . . . . . . . . |
$$ | O X . O 6 . . . . , . . . . . , . . . |
$$ | O . X O 8 . . . . . . . . . . . . . . |
$$ | X X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


So it is not so accurate to say this corner is unconditionally alive, as such phrases are normally used to refer to locally enclosed shapes. It would be more accurate to say it is alive due to weaknesses in the surroundings. As some exercises, is it alive when white has the following reinforcement? This is actually a quite common strategy in real games, to get one of these reinforcement stones in sente against some other group you are attacking which would then allow you to kill the corner.

Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . W . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . . . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . W . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . W , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . . . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . W . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . . . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . W . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . . . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Click Here To Show Diagram Code
[go]$$Wm1
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O . O . . . . . . . . . . . . . . . |
$$ | . . . W . . . . . . . . . . . . . . . |
$$ | . X . O . . . . . , . . . . . , . . . |
$$ | . . X O . . . . . . . . . . . . . . . |
$$ | . X X X O . . . . . . . . . . . . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Author:  eyecatcher [ Mon Jul 25, 2016 4:09 am ]
Post subject:  Re: really unconditionally alive? (from "style of Iyama...")
Uberdude wrote:
First point, I think you got 2 and 4 in wrong order for setup diagram:

Upps, yes i did ... :)



Thank you (both:) ) for answering my question so good and fast :)

This was really good to learn/understand ...black 8 in your first diagram for example was something i did not thought about at all... next time maybe :geek:

... and thank you for the exercises... will study them
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