Tsumego From Games 110 / Attempts

1st attempt 1st step  

 

tderz: Previously I thought that an unconditional connection was possible,
however this enables White to connect the 3 stones on the left,
or kill Black on the right.

While it would be no problem to live without ko,
Black therewith had not complied with the
proviso "Black cannot afford to let white save the white+circle stones."

Then my suggested solution is thus the previously rejected ko where Black can capture first. Now we needed to know which ko threats would be sufficient for White:

• the direct value of connecting the 3 stones is only about 12 points;
• the value of attacking a/o capturing the stones is of course much higher and in the same magnitude as the upper right group to be rescued.

Herman: Not all of the board is shown. In the game, that group is even bigger and will certainly die if it is cut off in sente.

I have found no move , no sequence which can avoid that White can chose above, % hence I fail to comply with the proviso.

That here is my best attempt: http://eidogo.com/#1396v47X

solution

Herman: It is hard to comment here on the content of the diagrams at eidogo, but I will try. First, lets consider this case:

Missed variation  

In your solution, you have at a, but you seem not to have considered b?

Missed variation (2)  

After , you only considered the capture at a, but not the move at b?

tderz: Both questions -> true :-(
Making diagrams might distract from finding true solutions,
but not evaluating B is scandalous !!! -> http://eidogo.com/#1WgFVLz4

Dieter's attempts

Var 1  

Alive

Var 2  

Alive

Var 3  

So White tries something different. @

Herman: Consider at , what then?

tderz: or at looks even easier ?

Var 3  

tderz: this var3 does not seem to derive from above diagram,
as is not at the place of capturing above.

Dieter: I misjudged it, clearly.

Herman: So now captures and black is dead :)

Var 3  

tderz: Such a kind of variation is in my SGF. However my variation is flawed, because his move (your Var1) is simple and simply better, as pointed out by Herman.

This looks like something you might want for a nice problem solution.

I haven't figured out Herman's caution though. I think White always suffers from the damezumari.

Herman: The caution means that in your var3 diagram is sente at (almost) any time white wants it to be

Dieter: Is it? I don't see that. But here is what might be a solution.

Herman: Sorry, typo, that should be 16. But when I tried to fix it, others were already editing :)

Moves 1 to 10  

Herman: What about at a?

Moves 11 to 16  

tderz: -> I put your suggestions in this SGF: http://eidogo.com/#2ImUZhjH

More attempts by Dieter

Moves 1 to 10  

Dieter: Let's just make that exchange first. is the key move.

Herman: Yes it is :-)

Moves 11 to 16  

Herman: Correct. The game it is from went similar, sadly (had I killed black, I would've won the tournament)

Game continuation  

Game continuation, cont'd  

Variation  

Bill: works as well, doesn't it?

Herman: Yep :-)