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TwoByThreeBox

 

Two By Three Box Discussion
   

[Diagram]
Diag.: 2 kills

I thought I was Captain Smooth by making my little 2x3 box, but I didn't recognize the death that lay waiting with white's 2. D'oh!

Why does it kill?

[Diagram]
Diag.: Why 2 kills

At this point, the best black can do is to trap three in a row, which is dead. For the most part, once you've lost both 2-2 points, you're dead in the corner.

-- Scartol

Both 2-2 points? ummm...


Note that this only works because of damezumari that occurs in the corner. On the side, or in the middle this is alive as it is:

[Diagram]
Diag.: "Captain, it's alive!" - black has one extra liberty.


[Diagram]
Diag.: White creates a ko:

RMDow?: The same is true for 2x3 in the corner with 2 or more external liberties (black is alive). When there is exactly 1 liberty, the best white can do is to play a ko to create BentFourInTheCorner Dieter: I disagree: White makes a two-stage ko. There is no BentFourInTheCorner in the sense that it is dead by the rules. This a ko fully played out.



[Diagram]
Diag.: White is dead.

unkx80: I have added this in response of a query in Kanazawa Solution 24, and I think it is appopriate to post it here.

In this diagram, black is dead.

No, this is not a seki. Why?


[Diagram]
Diag.: Explanation 1.

After white 1 and 3 fills up all the external liberties, the marked black stones are caught in a connect-and-die.


[Diagram]
Diag.: Explanation 2.

If black 1 prevents the connect-and-die at any point of the game, he turns his group into a straight three big eye instead and dies in gote.



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