Can Black kill this corner with my first move? Or maybe Bc1 not the key move?
Here is my read, mistakes and all.
1) If Wf1 (?) Bd1, forcing Wd2 then Bb2 threats to link out and WA2 or WA3 allows Black to play Bc2 followed by Bb1 to make bulky five, right?
2) If Wd1 Bc2 kills, right?
3) If Wc2 Bd1: then a) We1 (?) Ba3, Wa2 Bb1 kills, I think; but b) Wb1 lives, as far as I can tell, so I'm stuck here. Is Bd1 a mistake?
Kill corner?
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DrStraw
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Re: Kill corner?
There is a much easier way to approach this. The L+1 group lives or dies with sente. That means that in response to a white cannot play b and must play c. But then after d white cannot block, otherwise e kills. So, the two statements:
1. L+1 is sente.
2. After d the tesuji is e.
will, between them, pretty much answer all questions regarding this position. Of course, there are other moves to look at, but if you know these two things then everything becomes simple.
1. L+1 is sente.
2. After d the tesuji is e.
will, between them, pretty much answer all questions regarding this position. Of course, there are other moves to look at, but if you know these two things then everything becomes simple.
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).
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Uberdude
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Re: Kill corner?
A general piece of advice for how to approach tsumego. Start by playing from the outside to reduce the eyespace ("there is death in the hane"). Only after you have shown that doesn't work think about playing inside moves first.
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moyoaji
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Re: Kill corner?
That move is incorrect. The corner is actually ko for life.
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Last edited by moyoaji on Tue Jun 03, 2014 10:55 am, edited 1 time in total.
"You have to walk before you can run. Black 1 was a walking move.
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
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Aidoneus
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Re: Kill corner?
I started by looking at two hanes, but thought that Wc2 would make two eyes after Bb1--overlooking that Bg1 forces the right eye to be false since White can't protect with We1 because of Bc1.
Again, thank you both for the help. The corner tesujis give me so much trouble!
Again, thank you both for the help. The corner tesujis give me so much trouble!
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moyoaji
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Re: Kill corner?
Are you guys sure this kills? It still looks like ko to me.
From what I read of DrStraw's post, he isn't saying that 'e' kills, he says it is a powerful combination after 'd'. Which is true and which is what I posted in my analysis.
EDIT: If you are speaking of this variation, here is what I read -
From what I read of DrStraw's post, he isn't saying that 'e' kills, he says it is a powerful combination after 'd'. Which is true and which is what I posted in my analysis.
EDIT: If you are speaking of this variation, here is what I read -
Last edited by moyoaji on Tue Jun 03, 2014 11:20 am, edited 1 time in total.
"You have to walk before you can run. Black 1 was a walking move.
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
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HermanHiddema
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moyoaji
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Re: Kill corner?
"You have to walk before you can run. Black 1 was a walking move.
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
-
HermanHiddema
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Re: Kill corner?
@moyaji: white should answer 
with 
immediately, otherwise capturing 
is sente and black can get out.
with immediately, otherwise capturing is sente and black can get out.-
moyoaji
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Re: Kill corner?
If the possibility of getting out is included in this, then why does black not just captureHermanHiddema wrote:@moyaji: white should answer
with 
so he has enough liberties? Assuming that white has to block in some fashion then the variation at will work after the capture.I do agree, however, that if black plays
that white should play as 
."You have to walk before you can run. Black 1 was a walking move.
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
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DrStraw
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Re: Kill corner?
Yes I was. It is a standard tesuji which any midkyu needs to know.moyoaji wrote:
From what I read of DrStraw's post, he isn't saying that 'e' kills,
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).
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Uberdude
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Re: Kill corner?
Sorry to be picky Herman, but it's subtlety different as there are two stones not one at the lower right leg. In this case it doesn't make a difference to the status, but in other cases it can so this approach of simplifying to known corner shapes doesn't always work (though obviously it gives a good idea of things to try). For example:HermanHiddema wrote:After the hane, it is a JGroup, which dies like this:
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moyoaji
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Re: Kill corner?
James Davies considers this a J-Group.Uberdude wrote:Sorry to be picky Herman, but it's subtlety different as there are two stones not one at the lower right leg. In this case it doesn't make a difference to the status, but in other cases it can so this approach of simplifying to known corner shapes doesn't always work (though obviously it gives a good idea of things to try).
It's status problem 5 of the J-Group chapter in Life and Death. Page 111 in my copy.
I see that now. I am sorry. I failed to read one move farther than what I needed to.DrStraw wrote:Yes I was. It is a standard tesuji which any midkyu needs to know.
I did see the tesuji, but I did not see how it would succeed in that case. I was not familiar with this particular life and death problem.
"You have to walk before you can run. Black 1 was a walking move.
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
I blushed inwardly to recall the ignorant thoughts that had gone through
my mind before, when I had not realized the true worth of Black 1."
-Kageyama Toshiro on proper moves
-
HermanHiddema
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Re: Kill corner?
@moyoaji: You can prevent the escape and black still cannot live:
After Black is out of options, because a is answered with b, and c is answered with d
@Uberdude: I am aware of that, but this is generally considered a J-Group, AFAIK, and is shown as such on the page I linked.
After
Black is out of options, because a is answered with b, and c is answered with d@Uberdude: I am aware of that, but this is generally considered a J-Group, AFAIK, and is shown as such on the page I linked.