A question on a joseki refutation
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gostudent
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A question on a joseki refutation
It is well known that in the above sequence, black needs to play at (a) instead of (b), because of the following sequence:
followed by
However, it seems that black can create a capturing race by
At this point, the corner white group has four liberties, and the black group has six liberties. So white need to do something in the corner. One possibility is:
which, according to the discussion in this thread viewtopic.php?f=4&t=11505, the corner white group cannot make two eyes. In fact, black group seems to have a higher number of liberties, though I may have mis-counted.
Do I miss something obvious that white can do to kill the black stones easily? Thanks.
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Bki
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Re: A question on a joseki refutation
If White has the ladder, then this can work ( 
connect).
I'm pretty sure there is a better way though, just, it's late right now so...
Edit :
in your last diagram is wrong. Instead :
Big eye, you win the capturing race (if
at 
, then at and you have even more space.
Instead, if B attempt to set up a ko, this
thwart him (changing the order for and 
is also possible, but that's a needless sacrifice.
Edit 2: As an aside :
The J-group is sente (though I guess it might be a ko if the surrounding group isn't alive). is wrong, and should be one line below (descent rather than tiger mouth). Then you can avoid the ko, because Black must give you a four space big eye, and so you win once again the capturing race.
Edit : there are also possibility of winning by double ko, I think. But it's getting very late around here.
connect).I'm pretty sure there is a better way though, just, it's late right now so...
Edit :
in your last diagram is wrong. Instead :Big eye, you win the capturing race (if
at , then at and you have even more space.Instead, if B attempt to set up a ko, this
thwart him (changing the order for and is also possible, but that's a needless sacrifice.Edit 2: As an aside :
The J-group is sente (though I guess it might be a ko if the surrounding group isn't alive).
is wrong, and should be one line below (descent rather than tiger mouth). Then you can avoid the ko, because Black must give you a four space big eye, and so you win once again the capturing race.Edit : there are also possibility of winning by double ko, I think. But it's getting very late around here.
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EdLee
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gostudent
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Re:
Thank you for the input. Some thoughts:
Despite the big eyes, it looks like that white will lose the capturing race, because the outside liberty difference is too much:
or
This may be a bit better:
followed by
and black cannot connect. It will be difficult to read this out in actual game (at least for my level), though.
It looks like that black can connect to the outside stone by playing at (a).
Despite the big eyes, it looks like that white will lose the capturing race, because the outside liberty difference is too much:
or
at This may be a bit better:
followed by
take ko.and black cannot connect. It will be difficult to read this out in actual game (at least for my level), though.
EdLee wrote:
It looks like that black can connect to the outside stone by playing at (a).
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EdLee
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Hi GoStudent,
If W has this ladder, W can consider
descend and this var:
If W does not have the above ladder, W can consider the hane sequence and fight:
There may be situations where W wants to play this, despite the ladder:
Or, start a fight:
In your OP, you said "because of this sequence..." (Abridged & emphasis added
As you can see, it's not just 1, 2, or 3 sequences.
There are many sequences and variations starting with the 3rd line B hane.
Interesting and good to study.
If W has this ladder, W can consider
descend and this var:If W does not have the above ladder, W can consider the hane
sequence and fight:There may be situations where W wants to play this, despite the ladder:
at (a)Or, start a fight:
In your OP, you said "because of this sequence..." (Abridged & emphasis added
As you can see, it's not just 1, 2, or 3 sequences.
There are many sequences and variations starting with the 3rd line B hane.
Interesting and good to study.
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Uberdude
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Re: A question on a joseki refutation
This old chestnut again! So it's worth saying that hane rather than descent is usually the correct punishment for black's cheeky hane. See extensive discussion from viewtopic.php?p=161723#p161723.
Also in these variations under discussion now, even if white has a better move earlier that result of corner death is good for white if you can find time to cut on the left as it's super thickness.
Also in these variations under discussion now, even if white has a better move earlier that result of corner death is good for white if you can find time to cut on the left as it's super thickness.
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Bki
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Re: Re:
gostudent wrote:Thank you for the input. Some thoughts:
Despite the big eyes, it looks like that white will lose the capturing race, because the outside liberty difference is too much:
Hum...
Yeah, it doesn't work because
is atari. I will blame that on the late time at which I answered. but, like I said in an edit : 
connect.