BQM 257
This is problem 18 from goproblems.com (25k-15k level)
The correct answer according to the site is a. However I fail to see why b isn't also correct. If black b and white a, black can then continue by capturing the stone which is in atari. Why is it not a solution?
agro1986 (19k KGS)
zinger: The short answer is yes. This way also lives. For a somewhat long-winded discussion of which move is actually better, see /discussion.
Bill: The somewhat longer answer is yes, but.
Thanks to
White gets a huge ko threat to kill Black's group.
ilan: You are all wrong! The right move is c.
Xanthus: Why would this be better than a? W still has the ko-threat (or even 2 threats if B responds to taking of c with b). I'm not even sure if it is better than b, because it is a point worse if white defends, even though it might generate a (small) ko-threat for B.
Bill: I think this is an example of Ilan's wit. Good one, Ilan! ;-)
ilan: Thanks Bill! In fact, my solution is best according to LeastEfficientTsumegoSolutions? which I started thinking about while watching KGS lectures.
![[Diagram]](../../diagrams/16/e1264b9600416c2e3d3d9e1de8f31fae.png)
![[Diagram]](../../diagrams/2/58738497618275f10f55b13958167af4.png)
![[Diagram]](../../diagrams/33/e4bcf14337d1db1dc0b619d2438f9600.png)
lives, but it is a bad play.
![[Diagram]](../../diagrams/9/d4c7ff75e13435f58324146e7d536140.png)
![[Diagram]](../../diagrams/36/ecc5877812d970767943e8fb74c9094d.png)
2024 the Authors,
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