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LifeAndDeath

Referenced by
TwistedFour
BQM1Solution

 

Twisted four in the corner
Path: LifeAndDeath   · Prev: BentFourInTheCorner   · Next: TwoByThreeBox
    Keywords: Life & Death

1. Fewer than two outside liberties

[Diagram]
Fewer than two outside liberties

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


[Diagram]
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]
Two outside liberties

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


[Diagram]
Main line

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


3. Endgame implications

[Diagram]
Main line

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



Authors

  • Dieter


Path: LifeAndDeath   · Prev: BentFourInTheCorner   · Next: TwoByThreeBox
This is a copy of the living page "Twisted four in the corner" at Sensei's Library.
(OC) 2003 the Authors, published under the OpenContent License V1.0.