Gokyo Shumyo, Section 3, Problem 89 / Attempts

solution?  

solution?  

unkx80: in this solution don't look right, because kills (leading to the position at the end of variation 1).

variation 1  

xela: The marked stones are captured: black is dead.

variation 2  

xela: Is this the right response to ? Note that at would be a mistake, as black could throw in at and live by oiotoshi.

Edit: on second thoughts, no, at makes things more interesting, I'll need to think some more about this...

variation 2a  

atulab (15k): it looks as if I can prove 2 a and b are wrong

variation 2: refutation ?  

here threatens life with , which white prevents by the atari at , but white still needs to get his stones out of danger and black has time to get another eye by playing 10

variation 2a: refutation ?  

is very ugly (looks like bad shape to me ^^) but it threatens and and making two eyes at a: black is alive

can anyone find a flaw in my refutations or are they correct ?

unkx80: Your refutation does not look like a refutation to me. What if at a?

atulab: capture a stone at b ?

atulab: which makes a ko ^^

atulab: a little more 15K wisdom, this time aiming a the solution

variation 3  

white has the funny move a 1. white 2 being deadly, black plays here himself but is then squeezed and forced to play the ko at a note that black has a local ko threat at the squared points so there should be a better position (or my attempt is doomed ^^)

variation 3  

unkx80: I suspect you have not heard of double ko life? ;)