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LifeAndDeath

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SolutionToQuestio...
TwistedFour

 

Twisted four in the corner
Path: LifeAndDeath   · Prev: BentFourInTheCorner   · Next: TwoByThreeBox
   

1. Less than two outside liberties

[Diagram]
Diag.: Less than 2 outside liberties

If there are less than two outside liberties, White can turn this position into ko.


[Diagram]
Diag.: Main line

White 3 starts the ko. White can finish the ko by filling at the marked stone.



2. At least two outside liberties

[Diagram]
Diag.: Two outside liberties

If there are at least two outside liberties, Black is alive with 3 points.


[Diagram]
Diag.: Main line

Thanks to the two marked liberties, Black can atari at 4. Without one of those liberties, he would put himself into atari.


3. Endgame implications

[Diagram]
Diag.: Main line

When White reduces the outside liberties to 1, Black 2 or 'a' makes 3 points in gote, preventing the ko.



Authors

  • Dieter


Path: LifeAndDeath   · Prev: BentFourInTheCorner   · Next: TwoByThreeBox
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