Gokyo Shumyo, Section 6, Problem 1 / Attempts

[Diagram]

Black to play and connect underneath

This move stands out to me because 'a' does not add any liberties to the white group.

[Diagram]

Black to play and connect underneath

The atari at 9 allows B to cut off 8. Playing 6 at 10 allows 7 at 6, cutting off the white stones as well.

[Diagram]

Black to play and connect underneath

The atari at 'a' again forces white to connect at the marked stone, allowing black 'b' to kill off the white cutting stone.

[Diagram]

Black to play and connect underneath

3 @ the marked black stone. Playing 1 on the other side still fails, as W cannot bridge under due to a connect-and-die.

Let's examine other responses.

[Diagram]

Black to play and connect underneath

This permutation reverts to above.

[Diagram]

Black to play and connect underneath

Easy variation for 6: a and b are miai to save 1 and sever the chain of W stones connected to 4. The continuations are given:

[Diagram]

Black to play and connect underneath

4 at the marked spot; W's cutting stones are in a hopeless. situation.

[Diagram]

Black to play and connect underneath

B has 7 liberties, W is trapped and has only 4.


[Diagram]

Black to play and connect underneath

Little more complicated variation for 6. Pushing with 9 is key; if W plays a instead of blocking at 10, B connects underneath with 11 at 10.

[Diagram]

Black to play and connect underneath

If W insists on cutting B off by playing through 4, B returns the favor at 5, triggering a race. However, W only has 3 liberties to B's 5 or more. W cannot escape. 2 at 4 leads to 3 at 'a', postponing the inevitable.

[Diagram]

Black to play and connect underneath

unkx80: I am not sure about your claim that Black has at least 5 liberties. It seems to me that W6 and W8 causes Black to have only 2 liberties.


[Diagram]

Black to play and connect underneath

After B at 'a', W at 'b', B at 'c', d and e are miai to trigger the capturing race, reverting to previous diagrams.


[Diagram]

Black to play and connect underneath

This placement of 6 seems complicated. See continuation...

[Diagram]

Black to play and connect underneath

B sacrifices the marked stones to prevent W connecting at 'a'. If W connects at a, B at b is atari and W's position collapses.

[Diagram]

Black to play and connect underneath

5 at the marked spot. Instead, W saves his stones, but allows B to bridge under.

[Diagram]

Black to play and connect underneath

On second thought, seems like B@1 fails?


Attempt number 2!

[Diagram]

Black to play and connect underneath

Perhaps the move at 'a' is too early. Let's try at 1.

[Diagram]

Black to play and connect underneath

If W hanes to the right, a and b are miai to cut off at least 1 white stone, ensuring the connection

[Diagram]

Black to play and connect underneath

If W hanes to the left, 3 and the response at 4 play out slightly differently; now a and b are miai for black to cut, and b and c are miai for black to save the cutting stones. W's only hope is to play b.

[Diagram]

Black to play and connect underneath

Unfortunately, after 4, W's marked group is in atari and cannot escape.


[Diagram]

Black to play and connect underneath

If 4 here, this sequence follows. B11 @ a, W12 @ marked stone, B12 @ b, cutting off W2. I believe the 7-8 exchange can be omitted, but I don't see why B would do that.

[Diagram]

Black to play and connect underneath

4, 6 here reverts to the above

[Diagram]

Black to play and connect underneath

B11 @ a, W12 @ b, B13 @ c. White's stones have been cut off and are hopeless.


This is a copy of the living page "Gokyo Shumyo, Section 6, Problem 1 / Attempts" at Sensei's Library.
(OC) 2012 the Authors, published under the OpenContent License V1.0.
[Welcome to Sensei's Library!]
StartingPoints
ReferenceSection
About