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Opening problems for AI: Problem 13

Posted: Thu Jun 25, 2020 10:11 am
by Bill Spight
Another Takemiya special. :) The bots may not particularly like Cosmic Go™, but playing against it is challenging. ;) White was Kataoka Satoshi, the game, GoGoD 2012-03-29a.
Click Here To Show Diagram Code
[go]$$Wcm10 White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Kataoka made a standard play, which Elf reckons loses 14% to par.

Re: Opening problems for AI: Problem 13

Posted: Thu Jun 25, 2020 10:12 am
by Bill Spight
Kataoka played sanrensei.
Click Here To Show Diagram Code
[go]$$Wcm10 White sanrensei
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 1 . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . 2 O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
As we now know, White sanrensei is seldom right, if ever, but way back then it was certainly an attractive move.

Takemiya replied with the attachment, :b11:, but Elf thinks that that loses 11% to simply occupying the 3-3.

Click Here To Show Diagram Code
[go]$$Bcm11 Mainline for :b11:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . 3 . . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . 6 4 . . |
$$ | . . . . . . . . . . . . . . . . 5 . . |
$$ | . . . O . . . . . , . . . 7 . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . 2 . . O . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Black occupies one 3-3 point and then switches to a footsweep in the other corner. Next, :w14: braves the deep.

For :w10: Elf prefers to invade a corner.
Click Here To Show Diagram Code
[go]$$Wcm10 White invades a corner
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . 6 5 7 . . |
$$ | . . . . . . . . . . . . . O 9 2 1 . . |
$$ | . . . O . . . . . , . . . . . X 3 . . |
$$ | . . . . . . . . . . . . . X . 4 8 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . a . . O . . . . . |
$$ | . . . . . . . . . . . . . . 0 . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
After the :w10: invasion there follows a placid joseki, and then :b19: plays the footsweep in the other corner. :w20: extends to a.

These differences in evaluation are really what the opening is about. :)

Re: Opening problems for AI: Problem 13

Posted: Fri Jun 04, 2021 10:09 am
by dhu163
Speculatively:
Current position:
1. Seems that the 3-3 invasions R3, R17 are standard and good here. M4 also comes to mind. F3 as well. R6 seems overplay.

Opp to play
1. L4?

Past:
1. W ahead a little

Check:
1. I checked this shape in the past. Another variation is R17 R16 Q17 P16 N18
2. I didn't know B's follow up was 3-3.