OD1P - May 23 Problem / Solution

Sub-page of OD1PMay23Problem


Anonymous summary...


Black lives (without ko.)

Bad for white (can't play at a)  
3 is Tesuji  

Best for white. If W4 at W6, then B5 at B7. If W4 at a, then black makes life with B5, (although he might make bigger life with B6?)

Inferior 4 (B9 at black+circle)  

Trying to kill only lets black get bigger life.

Bad for white  

B3 saves the day again. W4 at W8 transposes to our previous line. If W4 at B5, then B5 at W4 makes B8 and a miai.

Double ko  

Even if white has infinite ko threats, black is alive. White never gets a chance to fill a, because black can always take one of the kos, and thus threatening to make unconditional life by taking the other.


Black makes a ko for life.

Ko (not small)  

B7 captures This is (probably?) the best way for black to play after B1.

Ko (continued)  

Black takes first.

B3 is too greedy  

This B3 fails, since W8 at B1 kills.


I am unsure how white counters this B3. a, b, c, and d are possibilities. After other moves, black makes life with d.


W2 and W4 are sente, W6 takes the vital point.

This B1 dies too  
Bulky five, so B1 dies  
This B1 seems to transpose into other lines...?  

This might work

Black lives, I hope...  

Black lives.

I think this would be white's response...  

This looks like black dies... the real solution is at the 2-2 point, as shown below? --Anon

Failure 1 (Dead)

Failure 1 (Dead)  

Black dies.

Failure 2 (Ko - Black can do better)

Failure 2 (Ko)  

B7 takes at black+circle. Next:

Failure 2 (continued)  

W1 takes back, and after B2 and W3 a ko fight ensues. Black can do better than that.

How about?  

B7 takes at black+circle, W8 at 2.
Bill: The writer was under the misapprehension that B7 could be played at 2. The corrected sequence shows that Black dies.

Or? (4 at 2, 7 at white+circle)  

Or? (Corrected.)  

W4 fills at black+circle.
Bill: Through B7 Black lives, but W4 is an error.

Attempt 3


Bill: B1 looks OK.
Then W2 - B7 is sente.
In a real game, I think that the ko (Failure 2) is often better than giving up so much for small life. :-)

Double ko  

Here is a variation I like. Black is alive in double ko.

B1 was a real blind spot for me. I had then expected W2 here, and Black still lives.

Solution 3  

OD1P - May 23 Problem / Solution last edited by on January 22, 2008 - 01:51
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