Gokyo Shumyo, Section 1, Problem 56 / Solution

[Diagram]

Main line

The first move is probably the hardest one. Why not 2-2 or 4-2 ? We'll investigate that later.

[Diagram]

Variation

If White enters at W2, Black closes the door with B3. Then W4 seems to be the best move for White, but with B5 and B7 Black gets just enough eyespace. After B9, Black is alive - a and b are miai. (Disclaimer: there may be mistakes in this variation.)


Actually, this problem looks harder than it is. When looking at it from White's standpoint, it is quite easy to find the correct move on the spot.

[Diagram]

Reference diagram

White can enter Black's EyeSpace from two sides: at a or b. Black has to find a move which protects against both. Let's analyze some failures first.

[Diagram]

Failure 1

Simply closing off at B1 is not good. W8 makes miai of a and b.

[Diagram]

Failure 2

If Black closes off the other side, White breaks in from the first. Up to B10, Black makes a (slightly modified) door group which is dead.

[Diagram]

Other candidates

Here a and b also fail to protect against W2. So let's investigate the last candidate, c.

[Diagram]

Failure 3

B1 here fails to protect against the jump to W2. His eye space is sufficiently reduced. The rest of the moves are for reference.


[Diagram]

Variation 1

If White plays W2 or a, Black protects at B3 and makes such nice shape that it isn't even necessary for Black to respond to W4. We'll analyze this in Gokyo Shumyo, Section 1, Derived Problem 56.


Next


This is a copy of the living page "Gokyo Shumyo, Section 1, Problem 56 / Solution" at Sensei's Library.
(OC) 2024 the Authors, published under the OpenContent License V1.0.
[Welcome to Sensei's Library!]
StartingPoints
ReferenceSection
About