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32

Zeiss isn't completely correct, this is actually the less common reason for omitting the I. The more common reason why I is often omitted where it would normally be expected between H and J is because in sans serif fonts the uppercase "I" is completely identical to the lowercase "l" (L). In a go board if you see a move noted in uppercase as I6 or lowercase ...


19

In most cases, where "I" is omitted between "H" and "J", it's to avoid confusion with number "1". It's also common to omit the letter "O" for the same reason (confusion with number "0", more of a problem in some fonts than others).


11

Yes, this is possible. It requires the living group to circle back on itself like this: $$Bcm0 $$ ............ $$ ...OOOOOO... $$ ..OOXXXXOO.. $$ .OOX.XX.XOO. $$ .OX.XOOX.XO. $$ .OXXO.OOXXO. $$ .OXXOO.OXXO. $$ .OX.XOOX.XO. $$ .OOX.XX.XOO. $$ ..OOXXXXOO.. $$ ...OOOOOO... $$ ............ Here, each of the eight black eyes is locally a false eye, but because ...


7

Four stones is an enormous handicap on a 9x9 board. With perfect play by Black, White probably can't make a living group. If you're taking four stones, you presumably aren't going to play perfectly. The main thing to do here is stay out of trouble. Connecting below 5 is a nice solid move. Playing to capture the two stones is fine, too. As long as you keep ...


6

I've read a couple of articles discussing the impact of AI on professional Go, the second one being a reply to the first one: Impact of Go AI on the professional Go world Impact of Go AI on the professional Go world, Response Some quotes from the first article: The second important change I see is the professional players’ race to learn from AI. (...) it’...


6

In order to capture a group, you need to deprive it of all "liberties," the empty spaces touching the stones. In this case, the southwest group has two liberties, on A1 and C2. However, as the rules don't allow you to leave any of your own stones without liberties at the end of your turn, you can't play on A1 due to suicide, and the same goes for ...


6

As the right most eye does not have a solid chain it is still vulnerable. This combined white's coverage on 8 means that when white takes E8 white will easily be able to move E9 into atari; after E8 white's next move would be F9, G8 or G9, which black cannot effectively block within the available two moves.


6

Rui Naiwei has won the Guksu (the 43rd open Guksu title in South Korea, 1999) and the Maxim Cup (2004). Wiki: https://en.wikipedia.org/wiki/Rui_Naiwei As for comparitive rankings, this article from 2016 may be of interest to you. AlphaGo’s win makes it the only non-male player in the top 75 world rankings. Yu, the first woman, is number 79, as of Friday. ...


6

Playing in the space above 82 would result in that black group having no liberties while the white groups surrounding it do still have liberties, so the group would immediately be captured by white. According to Wikipedia, most rulesets prohibit moves like that. If you play in the bottom right hole, on the other hand, that black group still has multiple ...


5

The White's are dead if the surrounding Black's are alive. The White's are two moves away from being captured by Black. White can make moves to prolong its dying but not prevent it.


4

It is possible depending on previous turns that some variants of the Superko rule would allow black to win that fight. For example, if black played A3, white might not be allowed to capture at A5 if that position had already appeared earlier in your game. However, even if that rule is in effect and relevant, I doubt it would be incorporated into the scoring ...


4

Achieving the statistically perfect komi is interesting, but generally the difference between winning by 1/2 a point or winning by 1/3 a point does not change a game result. We play in units of one stone (i.e., one point in area scoring), not 1/3 stone. I don't have my copy of Go Players Almanac so I can't readily check dates -- I'll try to update later -- ...


3

Just think about what happens when your stones get fully surrounded, as will eventually happen: The stone(s) at E9 will only retain a single liberty, the false eye, and you will need to fill that single liberty with a stone to connect E9 to the rest of the black group. And after that, only a single eye remains. That is the point of false eyes: They are ...


2

The Computer Go Server1 is currently a very active test bed for bots. The Computer Go page at Sensei’s Library refers, under Competitions, to various competitions including the Computer Go Server, with its own page at Sensei’s Library, which gives the URL1. On that site, you will find daily updated tables of bots for 9×9, 13×13 and 19×19, These refer to the ...


2

The theoretical answer depends whose rules you are using, because different countries use different rules, and have different ways of dealing with the multi-ko1 situation you describe. In practice this almost never arises, and keeping track is usually easy, as something else happens to change the whole-board state, such as a move on a previously unoccupied ...


2

Super Ko can be detected efficiently using Zobrist hashing. https://en.wikipedia.org/wiki/Zobrist_hashing https://www.gnu.org/software/gnugo/gnugo_11.html#SEC144 The idea is to pick a random 64-bit integer to represent each of the 2x19x19 = 722 positions on the board. The empty board has a hash value of 0. When you add a stone to the board you XOR the ...


2

The black group in the upper corner has two liberties, as does the main white group before you play that last piece. Therefore, if you had instead decided to play elsewhere on the board, white could have decided to capture the black group and done so before you could save it. With that final spot filled in, you are now guaranteed to capture the white ...


2

Guo Juan, Chinese pro 5 dan, won the EGC four times in a row in the 1990s. Xuefen Lin, pro 1 dan from China, won the US Open in 2005. Svetlana Shikshina, a Russian national playing at 3 dan in the Korean pro association, won the European Go Championship in 2006. I'm not sure, but I think Feng Yun (the other female pro 9 dan, along with Rui Naiwei mentioned ...


2

A corner invasion can in some cases can make a huge difference. In this case the play on th 3-3 point threatens to cut the white group in the upper left into three pieces, two of which have no chance at life and the third is in bad shape. That siad, I think the AI is a bit premature in declaring all these stones dead. A play by white to connect at the 4-3 ...


2

This seems like a mistake to me. I don't see a way to win the race. I wonder if the point was that White now has a stable group, so this is a failure for black. White can hane underneath the stone on the right side, and should probably be happy with that - Black was stronger here to begin with.


1

You are right that the top right belongs to White with correct play, but according to the programme Sabaki White wins by one point (because they have a captive). It is conceivable, but somewhat unlikely, that White could make enough errors for Black to win. The score Sabaki calculates the score like this for area scoring: and like this with territory ...


1

Edits: corrected my miscount of Black area, possible White gain If my calculations are right, you seem to have lost or won depending on the rules in force, but you had a chance in any case! Your score In your position, using area scoring, I count your central group as 40 points as follows: Counting in vertical pairs left to right two horizontal lines at a ...


1

I cannot tell you, what move is best, but here is how I (around 7k) think about it: $$Bcm4 $$ +---------+ $$ |.........| $$ |.........| $$ |..X...X..| $$ |.........| $$ |....,.2..| $$ |...c1Xa..| $$ |..X3OOX..| $$ |.....de..| $$ |.........| $$ +---------+ The white move at G5 is obviously a threat to cut at G4. I guess, that won't surprise you. The threat ...


1

Disclaimer I am about 7 kyu, and seldom play 9×9, so I defer to those with higher ranks or more experience. How would KataGo play? I asked KataGo, running as an engine for Sabaki, and this is what it thinks: The first image shows that it rates the connection at G4 as best, expecting you to win by ~60 points if you play there; the second shows how it ...


1

An earlier question about database for 9x9 games contains a link to a database for 19x19 games: http://ps.waltheri.net/


1

The previous answers assume Black connects at S3, but what happens when Black initially sacrifices four stones? White tries to kill everything ... $$Bcm1 $$ |...,....., $$ |.......... $$ |.......... $$ |.XXX...... $$ |9OOOX..... $$ |.OXXOO.... $$ |.OXO....., $$ |8OXOO2.... $$ |6X7X134... $$ |.XXX.5.... $$ +---------- and fails. White cannot play at ...


1

Short answer How can a ko fight be “asymmetric”? By offering one player a strong incentive to start it. When a ko is asymmetric You are right that once the ko is started, the result is equally valuable to both sides. Where the asymmetry comes in is when one player, considering whether to start the ko, compares three local outcomes: They start the ko and ...


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