It is currently Fri Oct 22, 2021 10:10 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 391 posts ]  Go to page 1, 2, 3, 4, 5 ... 20  Next
Author Message
Offline
 Post subject: Japonese counting
Post #1 Posted: Fri Aug 06, 2021 3:54 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
Click Here To Show Diagram Code
[go]$$B Black to play
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X . O O O O . |
$$ | X O X O X O O O . |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

Black to play in japonese rules. How do you finish the game to get the best result?


This post by Gérard TAILLE was liked by: ElomKW
Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #2 Posted: Mon Aug 09, 2021 5:12 am 
Lives in sente

Posts: 1000
Liked others: 0
Was liked: 169
I suspect the lack of response is because not understanding what is meant by "best result" in a situation like this.

Maybe we just aren't seeing why all the outside black stones won;t die.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #3 Posted: Mon Aug 09, 2021 5:50 am 
Judan

Posts: 5503
Liked others: 0
Was liked: 744
Speaking for myself, I have not responded because, by experience, writing down a careful rules application for this particular position requires ca. 3 to 4 hours.

(The term "counting" means the mechanical rearrangement or other physical procedure to count the score. The term "scoring" means the system or method by which the rules define what the score is for the game end situation determining the winner. The thread title means "Japanese scoring" while the counting procedure is immaterial for the OP's question. In ordinary, non-go English, the words counting and scoring are to some extent interchangeable. In go terminology since 1993, however, they have become terms with different meanings.)

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #4 Posted: Mon Aug 09, 2021 6:18 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
Mike Novack wrote:
I suspect the lack of response is because not understanding what is meant by "best result" in a situation like this.

Maybe we just aren't seeing why all the outside black stones won;t die.

You are right Mike. I think I failed to explain what was the problem in realtion with the rules.
Surely Robert is right concerning the wordings "counting" or "scoring". I am not quite fluent in english but I do my best.

Let me propose a far simplier (and more efficient?) position:

Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | . X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

Black to play. Obviously cannot save her stones on the top. My feeling is that black must play
Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | 2 X 4 X 6 X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | 1 O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]
:b3: pass
:b5: pass
and white wins by 11 points.

But I suspect it is only the feeling of an old player using J49 rule.
What about J89 rule? I am not sure but now the best sequence seems:
Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | 2 X 4 X 6 X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]
:b1: pass
:b3: pass
:b5: pass
and white wins by 10 points.

I am not sure of my rule interpretation. Thank you for an expert able to clarify the situation in J49 and in J89 contexts?

What is the point?
Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | a X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

After :b1: pass :w2: pass the status of the black stones at the top is given by the confirmation phase and in this phase black can play at "a" in the top left corner and I do not see how white can kill the black stones. This defence does not exist in normal play because in the loop created black gives one more prisoner at each cycle. In confirmation phase however, the prisoners are not counted are they?

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #5 Posted: Mon Aug 09, 2021 8:16 am 
Judan

Posts: 5503
Liked others: 0
Was liked: 744
Black 1 at A7 is another start to be considered.

J49? Serious?

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #6 Posted: Mon Aug 09, 2021 9:40 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
RobertJasiek wrote:
Black 1 at A7 is another start to be considered.

J49? Serious?


OK Robert, let's begin by considering only J89.
Click Here To Show Diagram Code
[go]$$Bc
$$ -----------------
$$ | 1 X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]


You propose black 1 at A7. What score do you expect to reach with this move? A white win by 10 points or 11 points or ?
It looks to me that this move loses one point but I may be wrong OC. Can you clarify how you finish the game after this move? IOW when will begin the confirmation phase?

Surely white expects
Click Here To Show Diagram Code
[go]$$Bc
$$ -----------------
$$ | 1 X 2 X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

Click Here To Show Diagram Code
[go]$$Bc
$$ -----------------
$$ | 4 3 O X . X O |
$$ | . O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #7 Posted: Mon Aug 09, 2021 10:00 am 
Judan

Posts: 5503
Liked others: 0
Was liked: 744
I have not studied the sequences but you just may not ignore A7 in your study. If it should be futile, you must prove it. Making assumptions is not applying the rules.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #8 Posted: Mon Aug 09, 2021 10:31 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
RobertJasiek wrote:
I have not studied the sequences but you just may not ignore A7 in your study. If it should be futile, you must prove it. Making assumptions is not applying the rules.


Yes Robert. In my post https://lifein19x19.com/viewtopic.php?p=266383#p266383 I try to explain why this move black in A7 loses one point due to a cycle with one more black prisoner.
OC we must apply the rules and it is really my question with my example.

I suggest finishing the game by:
Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | 2 X 4 X 6 X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]
:b1: pass
:b3: pass
:b5: pass
and white wins by 10 points.

but because I am not completly sure of my understanding of the rule I ask to the experts if this sequence and this count is really the best result for both.
You see the curiosity here? In normal play white do not need to add a move to kill black stones, but, due to the confirmation phase, white must play three moves before the end of the game in order to declare the black stones really dead ;-)

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #9 Posted: Mon Aug 09, 2021 11:59 am 
Lives in sente

Posts: 1000
Liked others: 0
Was liked: 169
First of all, I object to the "simplification". Totally different problem. In the first example, under consideration is whether black can prevent the large white group from becoming unconditionally alive, because if so, it's all over(white can fill the upper left ko(s) and black has no ko threats after the one to live on the top is used.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #10 Posted: Mon Aug 09, 2021 2:51 pm 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
Mike Novack wrote:
First of all, I object to the "simplification". Totally different problem. In the first example, under consideration is whether black can prevent the large white group from becoming unconditionally alive, because if so, it's all over(white can fill the upper left ko(s) and black has no ko threats after the one to live on the top is used.


It is not clear to me what you mean here by "unconditionally alive". this wording make sense if it exists a rather unknown environment typically with potential ko threats. Here all the board is known and we know it does not exist any ko threat.

In my first example the black group at the top is dead. The problem is not to prove black stones are dead but rather to find the sequence which gives the best result.

As I said before my example is not that efficient because after:
Click Here To Show Diagram Code
[go]$$B Black to play
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X 2 O O O O a |
$$ | X O X O X O O O 1 |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]
I am worried by the dame at "a".

Because of that I have to improve the position. The following one is far better:

Click Here To Show Diagram Code
[go]$$B Black to play
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X X X O O O X |
$$ | X O X O O . O O . |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

What is the best sequence for both?

If I am not wrong there are a strong relationship with the following position I proposed:
Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | . X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #11 Posted: Mon Aug 09, 2021 9:46 pm 
Lives in gote

Posts: 380
Liked others: 0
Was liked: 32
I think in the simpler position B don't want to pass since then W can pass too and have no problems (B dead). B needs to throw in once to force W to capture in the main game (costing him points).

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #12 Posted: Mon Aug 09, 2021 9:57 pm 
Lives with ko

Posts: 206
Liked others: 17
Was liked: 20
Rank: panda 4 dan
IGS: kvasir
I thought this was a question if white needs to play zero, one or two moves on the inside. For example something like this:

Click Here To Show Diagram Code
[go]$$B :b5: Pass :b7: Pass :w8: Pass ...
$$ ---------------------
$$ | O X 4 X O O O 6 X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X 2 O O O O 3 |
$$ | X O X O X O O O 1 |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Or if white just passes if black can force white to play the last move (and possibly force white to play the last move twice in exchange for black passes).

For example:

Click Here To Show Diagram Code
[go]$$B :w4: Pass
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X 2 O O O O 3 |
$$ | X O X O X O O O 1 |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ---------------------
$$ | O X . X O O O . X |
$$ | 1 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | 2 O X O O O O O X |
$$ | X O X O X O O O X |
$$ | 3 O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]



Click Here To Show Diagram Code
[go]$$W
$$ ---------------------
$$ | 1 X . X O 3 O 2 X |
$$ | 4 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X O O O O O X |
$$ | . O X O X O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


...and this position is starting to get similar to the second position by Gérard. Possibly the players fills the liberties directly or cycle the ko while filling the liberties, and white always refuses to play extra moves on the inside.


As far as I can see this is an interesting ko study that doesn't necessarily have anything to do with specific rule differences, in the endgame white may get off easily if there is no penalty for finishing the ko but similar situations happen in middle game kos were white may find it difficult to finish the ko immediately. Basically, it appears to be a ko situation in which white can clearly win a capturing race by making an eye, but if white refuses to finish the ko he can lose the advantage because the ko can potentially become direct for black to capture.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #13 Posted: Mon Aug 09, 2021 10:46 pm 
Lives in sente
User avatar

Posts: 1203
Liked others: 11
Was liked: 136
Rank: German 1 Kyu
Just returned from walking the labrador. His name is Honte :razz:

So ...

Click Here To Show Diagram Code
[go]$$W Status confirmation for Black's groups
$$ -----------------
$$ | . X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O B B B B B |
$$ | . O B 1 3 B . |
$$ | O O B 5 7 B B |
$$ | B B B 9 . B . |
$$ -----------------[/go]

:bc: is alive, as it cannot be captured, even if White moves first.

Click Here To Show Diagram Code
[go]$$W Status confirmation for Black's groups
$$ -----------------
$$ | 1 Z 3 Z 5 Z O |
$$ | Z O Z Z Z Z O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

:bx: are all dead, as they can be captured.

Click Here To Show Diagram Code
[go]$$B Status confirmation for White's group
$$ -----------------
$$ | 2 X 4 X 6 X W |
$$ | X W X X X X W |
$$ | W W W W W W W |
$$ | 1 W X X X X X |
$$ | . W X . . X . |
$$ | W W X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

:wc: is alive, as it cannot be captured, even if Black moves first.


@ Gérard: White should NOT pass her first move in the Nihon Kiin 1989 Rules status confirmation! ;-) ;-) ;-)

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by four amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #14 Posted: Tue Aug 10, 2021 2:50 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
Kvasir, your analysis is exactly what I had in mind :)

kvasir wrote:
I thought this was a question if white needs to play zero, one or two moves on the inside. For example something like this:

Click Here To Show Diagram Code
[go]$$B :b5: Pass :b7: Pass :w8: Pass ...
$$ ---------------------
$$ | O X 4 X O O O 6 X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X 2 O O O O 3 |
$$ | X O X O X O O O 1 |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


That's true. When I built the problem I just forget to take into account the dame :b3: and, due to this dame, I cannot get the result I expected and this sequence was unexpected for me.

kvasir wrote:
Click Here To Show Diagram Code
[go]$$B :w4: Pass
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X 2 O O O O 3 |
$$ | X O X O X O O O 1 |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ---------------------
$$ | O X . X O O O . X |
$$ | 1 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | 2 O X O O O O O X |
$$ | X O X O X O O O X |
$$ | 3 O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$W
$$ ---------------------
$$ | 1 X . X O 3 O 2 X |
$$ | 4 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X O O O O O X |
$$ | . O X O X O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


That is the sequence I expected :clap:

In order to avoid the unexpected sequence mentionned at the beginning of this post I proposed a slight change in the initial position.
My modified position is the following:

Click Here To Show Diagram Code
[go]$$B Black to play
$$ ---------------------
$$ | O X . X O O O . X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | . O X X X O O O X |
$$ | X O X O O . O O . |
$$ | X O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Now the expected sequence is
Click Here To Show Diagram Code
[go]$$B Black to play
$$ ---------------------
$$ | O X . X O O O . X |
$$ | 3 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | 4 O X X X O O O X |
$$ | X O X O O 2 O O 1 |
$$ | 5 O X X X X X X X |
$$ | X O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$B
$$ ---------------------
$$ | 6 X . X O 8 O 7 X |
$$ | X O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | . O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]


Click Here To Show Diagram Code
[go]$$Bm9
$$ ---------------------
$$ | O X . X 2 O . X X |
$$ | 1 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | . O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

and we reach a position identical to the simplication I proposed.
I will try to analyse this simpler position in an other post, and please try to take into account only my modified position.


This post by Gérard TAILLE was liked by: kvasir
Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #15 Posted: Tue Aug 10, 2021 3:39 am 
Lives in sente

Posts: 821
Liked others: 14
Was liked: 37
Rank: 1er dan
jann wrote:
I think in the simpler position B don't want to pass since then W can pass too and have no problems (B dead). B needs to throw in once to force W to capture in the main game (costing him points).


Click Here To Show Diagram Code
[go]$$B Black to play
$$ -----------------
$$ | . B . B . B O |
$$ | B O B B B B O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]


OK Jann, let's see what happens if both players pass in the position above and here is really the rule interpretation issue ;-)

I imagine the following dialog:
White : your black stones at the top are dead
black : no, if I you do not add at least one move, they are living. IOW if you want to kill them you have to resume the game and add at least one move.
white : no I do not want to add moves (because I will lose points).
black : OK in that case we enter the confirmation phase. Because you refuse to add a move that means you consider black stones are dead even if it is black to play right?
White : yes
Black : in that case I start the confirmation phase and you will try to kill me, correct?
White : yes, let's go

Click Here To Show Diagram Code
[go]$$B Confirmation phase
$$ -----------------
$$ | 1 X 2 X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]


Click Here To Show Diagram Code
[go]$$B Confirmation phase
$$ -----------------
$$ | 4 3 O X . X O |
$$ | 5 O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]


Click Here To Show Diagram Code
[go]$$B :w6: pass for the ko, :b7: connect the ko
$$ -----------------
$$ | 7 X . X . X O |
$$ | X O X X X X O |
$$ | O O O O O O O |
$$ | . O X X X X X |
$$ | . O X . . X . |
$$ | O O X . . X X |
$$ | X X X . . X . |
$$ -----------------[/go]

and the cycle will go for ever. Does that prove that white cannot kill black stones? That is the point.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #16 Posted: Tue Aug 10, 2021 3:42 am 
Judan

Posts: 5503
Liked others: 0
Was liked: 744
Analysis so far misses the following:

- One sequence per status might not be enough.
- Play before successive passes can result in different scoring positions, of which each must be analysed by hypothetical play to then evaluate strategy before successive passes.
- Different Japanese rulesets require different applications.

3-4 hours analysis time is the lower bound. Spending a few minutes on random thoughts does not do it.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #17 Posted: Tue Aug 10, 2021 4:33 am 
Lives in sente
User avatar

Posts: 1203
Liked others: 11
Was liked: 136
Rank: German 1 Kyu
Gérard TAILLE wrote:
black : OK in that case we enter the confirmation phase. Because you refuse to add a move that means you consider black stones are dead even if it is black to play right?
White : yes
Black : in that case I start the confirmation phase and you will try to kill me, correct?
White : yes, let's go


As I already stated above, the text in red is mistaken, at least if you want to apply Nihon Kiin 1989 Rules.

The STATUS CONFIRMATION of each and every single group of stones on the board starts with the FINAL POSITION of "PLAY".
It does NOT matter at all which side put the last stone onto the board.
There is NO conjunction between PLAY and STATUS CONFIRMATION.

"... cannot be captured by the opponent, ..." implies that White starts the status confirmation for a Black group.
If Black ever wanted to add a stone before, he would have had to do it during "PLAY".

+ + + + + + + + + + +

For comparison:
If STATUS CONFIRMATION is entered with the central point of a genuine Nakade shape unoccupied (both players had a blind spot here), the status of the relevant group is "dead", NOT "alive".

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by four amateurs)

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #18 Posted: Tue Aug 10, 2021 4:51 am 
Lives in gote

Posts: 380
Liked others: 0
Was liked: 32
I also think J89 analysis starts with attacker.

Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #19 Posted: Tue Aug 10, 2021 5:22 am 
Lives in sente
User avatar

Posts: 1203
Liked others: 11
Was liked: 136
Rank: German 1 Kyu
Gérard TAILLE wrote:
I will try to analyse this simpler position in an other post, and please try to take into account only my modified position.

Click Here To Show Diagram Code
[go]$$B Final position of PLAY
$$ ---------------------
$$ | . X . X O O . X X |
$$ | X O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | . O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

+ + + + + + + + + +

Click Here To Show Diagram Code
[go]$$W status confirmation for Black's group
$$ ---------------------
$$ | 1 X 3 X O O 4 X X |
$$ | X O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | 2 O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

Click Here To Show Diagram Code
[go]$$W status confirmation for Black's group
$$ ---------------------
$$ | O . O X 5 7 X X X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | X O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

:b6: PASS for lifting the ko ban

MISTAKEN earlier version (see jann's posting below).
Click Here To Show Diagram Code
[go]$$W status confirmation for Black's group
$$ ---------------------
$$ | O 6 O X 5 . X X X |
$$ | 8 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | X O X O O O O O X |
$$ | X O X X X X X X X |
$$ | 7 O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

Click Here To Show Diagram Code
[go]$$Bm10 status confirmation for Black's group
$$ ---------------------
$$ | 1 X 2 X O . X X X |
$$ | X O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | . O X O O O O O X |
$$ | . O X X X X X X X |
$$ | O O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

Click Here To Show Diagram Code
[go]$$Bm12 status confirmation for Black's group
$$ ---------------------
$$ | 2 1 O X O . X X X |
$$ | 3 O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | . O X O O O O O X |
$$ | . O X X X X X X X |
$$ | O O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]
ad infinitum ...

+ + + + + + + + + +

Click Here To Show Diagram Code
[go]$$B status confirmation for White's group
$$ ---------------------
$$ | 2 X 4 X O O 5 X X |
$$ | X O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | 1 O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

Click Here To Show Diagram Code
[go]$$B status confirmation for White's group
$$ ---------------------
$$ | O 6 O X . . X X X |
$$ | . O X X X X X X X |
$$ | O O O O O O O O O |
$$ | O O X X X O O O X |
$$ | X O X O O O O O X |
$$ | X O X X X X X X X |
$$ | . O X . . . . X . |
$$ | O O X . . . . X X |
$$ | O O X . . . . X . |
$$ ---------------------[/go]

+ + + + + + + + + +

Click Here To Show Diagram Code
[go]$$B Result of STATUS CONFIRMATION
$$ ---------------------
$$ | . Z . Z W W . Z Z |
$$ | Z W Z Z Z Z Z Z Z |
$$ | W W W W W W W W W |
$$ | W W X X X W W W X |
$$ | . W X W W W W W X |
$$ | Z W X X X X X X X |
$$ | . W X . . . . X . |
$$ | W W X . . . . X X |
$$ | W W X . . . . X . |
$$ ---------------------[/go]
All of Black's stones in question are dead.

_________________________________
EDITED

_________________
The really most difficult Go problem ever: http://igohatsuyoron120.de/index.htm
Igo Hatsuyoron #120 (still unresolved by professionals, maybe solved by four amateurs)


Last edited by Cassandra on Tue Aug 10, 2021 6:25 am, edited 4 times in total.
Top
 Profile  
 
Offline
 Post subject: Re: Japonese counting
Post #20 Posted: Tue Aug 10, 2021 5:49 am 
Lives in gote

Posts: 380
Liked others: 0
Was liked: 32
In confirmation cannot retake ko without passing for it.

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 391 posts ]  Go to page 1, 2, 3, 4, 5 ... 20  Next

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: Bing [Bot] and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group