For lessons, as well as threads about specific moves, and anything else worth studying.
xela
Lives in gote
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by xela Sun Oct 13, 2019 4:46 am
One of these problems is not like the others...
Book 1 of the
LCH tesjui set is mostly "spot the key point" capturing races, where the continuation is a one-way street. But problem 92 seems to have a lot more variations than anything else in the book. As far as I can tell, there are actually two ways for black to capture the white stones on the left. Does anyone else agree?
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
Bki
Lives with ko
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by Bki Sun Oct 13, 2019 10:20 am
The first thing that appear to work that I see is this :
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
Black only has two liberties and can't really increase them so an atari is the first thing to look at.
at "a" obviously fail because it's the corner, so trying for a ko seems to be white's strongest resistance.
increase liberties and threaten to live in the corner which would capture the six white stones, so
is forced then
win the capturing race
Next some other moves that might be worth exploring but fail :
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
And there's this one which I thought failed but might actually not :
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play. gains a liberty so black win
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
Being clver and trying to set up a ko ultimately fail
xela
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by xela Sun Oct 13, 2019 3:56 pm
Thanks bki, looks good to me. Your very first diagram is the variation diagram from the book (white has a less tricky but more profitable response which is given as the main line). All your failure variations are not in the book, and I agree that they fail. Your very last diagram is given in the book as failure, but I agree with you that it succeeds.
Bki
Lives with ko
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by Bki Mon Oct 14, 2019 3:52 am
By the way, the tesuji-looking
in the following is why I thought this second variation failed initially :
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
But after
, black make an eye and white can't ever capture black.
at C2 also obviously fail for the same reason, and anything else fail by simply counting liberties.
Knotwilg
Oza
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by Knotwilg Mon Oct 14, 2019 4:17 am
This is what I saw:
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
Either I have a blind spot, or this line is rejected as White get too many free points
$$c Black to play.
Click Here To Show Diagram Code [go]$$c Black to play.
This is probably the main line: White forces a capture in sente
xela
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by xela Mon Oct 14, 2019 5:31 am
Yep, your second diagram is the first answer diagram in the book. I guess it's easier to read out, even if it does let white have a bigger corner.
SoDesuNe
Gosei
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by SoDesuNe Mon Oct 14, 2019 10:18 am
Interesting, that the hane-variation was considered first by so many. My eyes immediately went to make the guzumi : D
at "a" obviously fail because it's the corner, so trying for a ko seems to be white's strongest resistance. 
increase liberties and threaten to live in the corner which would capture the six white stones, so 
win the capturing race
in the following is why I thought this second variation failed initially :
