Capturing Race Exercise 24 / Attempts

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Attempt #1 -ProtoDeuteric



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Attempt #1 -White wins this way?

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Attempt #1 - A ko

unkx80: There is a ko. But I think I have seen this problem before, so I think ko is not the solution.


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Attempt #2 (B11 at the marked stone)

ProtoDeuteric: I hate to say it, but this was actually my first reading. I saw the B3 in the Attempt #1 diagram because I got really greedy. This still probably wrong, so I might not need to be so ex post facto righteous.

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Attempt #2 - Still a ko

unkx80: W4 is a tesuji. In the end, B7 has to make a throw-in ko. Nice attempts anyway. =)


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Oki

Bill: I think W2 is a good reply.

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Extra liberty

Bill: B3 is a simple reply. Now if W4, B5 wins, since W8 becomes a liberty.


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tderz: Having seen above, I also considered B1 here:
(after all you think Black should be able to pull off something)

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tderz: W2 looks bad, it gives Black good opportunities

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i) no ko

tderz: no ko after B5

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i-1)

tderz:

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tderz: ko in favour for Black (captures first)
(i.e. better than unkx80's ko. This is due to White's bad W2 above)

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ii)

tderz: this B3 should revert to variations of ProtoDeuteric above.

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ii-1)

tderz: is it??
W6 at a

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ii-2)

tderz: W4 is a mistake
W6 at a

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iii)

tderz: also considering B3 here...

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iii)

tderz: B has lost

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iv)

tderz: B3 creates 5 liberties for Black, but doesn't take one away from White.

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iv-1)

tderz: W4, taking outside liberties,
should revert to some above variations.

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iv-1)

tderz: B9 at a
favourable ko for Black


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tderz: Question: both moves a, b can thus lead to kos (un/favourable), wins or losses, depending on White moves (correct or flawed);
is there still one move better, or does it not matter?

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Solution?

unkx80: I think this might be the intended solution.

Truly impressive, unkx80!
Now I remember having seen once such a problem type.
Obviously I have not ubderstood and absorbed it.

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Solution?

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Solution?


This is a copy of the living page "Capturing Race Exercise 24 / Attempts" at Sensei's Library.
(OC) 2014 the Authors, published under the OpenContent License V1.0.
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