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Shapes to remember (SDK level)

https://lifein19x19.com/viewtopic.php?t=16894

Page 7 of 12

Re: Shapes to remember (SDK level)

Posted: Sun Aug 15, 2021 4:37 am
by kvasir
Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . O O X |
$$ | . . . X . . . . . . . . . O O O O X . |
$$ | . . O . . X . . X . . . . O . O X X X |
$$ | . . . O . . . . . , O O O . . , O X . |
$$ | . . . . . . . . . . O . . . . O X X X |
$$ | . . O . . . . . . X X O O . . O O O X |
$$ | . . . . . . . . . X O O O O . . . O O |
$$ | . . . . . . . . . . X O O . . O O O . |
$$ | . . . . . . . . . . X . O O O O O O X |
$$ | . . . , . . . . . , . X X O O X X O X |
$$ | . . O . . . . . X . . . O O X . X X . |
$$ | . . . . . . X . O X . . X X . X . . . |
$$ | . . . . . X . . O . X . . . . . . . . |
$$ | . O . O . 3 . . . . . X . . . . . . . |
$$ | . O X O . X . O O . O . . X . X . . . |
$$ | . X O O . . X X 2 , O X X O X , . . . |
$$ | X . X O . O . 1 X . O X O O O X . . . |
$$ | . X X X O . . O X X O O O O X . X . . |
$$ | . . . . . . . . . . . . . X . X . . . |
$$ ---------------------------------------[/go]
I am not confident about going directly to 3 but black is unlikely to play 2 :roll:

Re: Shapes to remember (SDK level)

Posted: Thu Aug 19, 2021 12:46 am
by jlt
Position #56: how to respond to the crosscut?
Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . X . . X . . . . O O X . . . |
$$ | . . W X . . . . . , . . O X . X . . . |
$$ | . . X O . . O . . . . . O X . . . . . |
$$ | . . . . . . . . O . . . . X . . . . . |
$$ | . . . X . . O . . . . . . . . O . . . |
$$ | . . . . . . . . X . . . . . . . . . . |
$$ | . . . X . . O . . . . . . . . . . . . |
$$ | . . . , . . . . X , . . . . . , . . . |
$$ | . . X . . . O . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . O . . X . . . . . . . . . . . |
$$ | . . X . . . . . X . . . . . . . . . . |
$$ | . . . X X X X X O O . . . . . , O . . |
$$ | . . . O . . O O . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Answer
Click Here To Show Diagram Code
[go]$$Bc answer
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 7 . X . . X . . . . O O X . . . |
$$ | . . O X . . . . . , . . O X . X . . . |
$$ | . . X O 1 . O . . . . . O X . . . . . |
$$ | . . 3 2 4 6 . . O . . . . X . . . . . |
$$ | . . . X 5 . O . . . . . . . . O . . . |
$$ | . . . . . . . . X . . . . . . . . . . |
$$ | . . . X . . O . . . . . . . . . . . . |
$$ | . . . , . . . . X , . . . . . , . . . |
$$ | . . X . . . O . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . . . O . . X . . . . . . . . . . . |
$$ | . . X . . . . . X . . . . . . . . . . |
$$ | . . . X X X X X O O . . . . . , O . . |
$$ | . . . O . . O O . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Shapes to remember (SDK level)

Posted: Mon Aug 23, 2021 9:37 am
by jlt
Position #57, another shape move, from a Fox 2d game. White to play.
Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O X X X . . . X X O . . . . . . |
$$ | . . . O O O . X . . O . O . O X . . . |
$$ | . . O , . . . . . , O . . . O , X O . |
$$ | . . O X . . . X . . . . . . . O O . O |
$$ | . . X X . . . . . . . . . . . O X O O |
$$ | . . . . . . . O . . O . . O O X X X O |
$$ | . . . . . . . . . . X O O X X . O X O |
$$ | . . . . . . . . . O O X X . X O . . X |
$$ | . . . X . . . . . , . . . X . X X X . |
$$ | . . . . . . . . . . O X X . X . . . . |
$$ | . . . . . . . . . . X O X . . . O . . |
$$ | . . X . X . . . . . X O . . X . . . . |
$$ | . . . . . . . . O . X O . O O O . . . |
$$ | . . . X O . . . . O X O . X . . . . . |
$$ | . . . X O . . . O X X O . . O O O O O |
$$ | . . X O O . . . O X . O . X . X O X X |
$$ | . . X X O . . . O X . . X . . X X . . |
$$ | . . . . . . . . . X . . . . . . . X . |
$$ ---------------------------------------[/go]
Answer:
Click Here To Show Diagram Code
[go]$$Wc The marked stones are captured
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O X X X . 1 3 B B O . . . . . . |
$$ | . . . O O O . X 2 . O . O . O X . . . |
$$ | . . O , . . . . . , O . . . O , X O . |
$$ | . . O X . . . X . . . . . . . O O . O |
$$ | . . X X . . . . . . . . . . . O X O O |
$$ | . . . . . . . O . . O . . O O X X X O |
$$ | . . . . . . . . . . X O O X X . O X O |
$$ | . . . . . . . . . O O X X . X O . . X |
$$ | . . . X . . . . . , . . . X . X X X . |
$$ | . . . . . . . . . . O X X . X . . . . |
$$ | . . . . . . . . . . X O X . . . O . . |
$$ | . . X . X . . . . . X O . . X . . . . |
$$ | . . . . . . . . O . X O . O O O . . . |
$$ | . . . X O . . . . O X O . X . . . . . |
$$ | . . . X O . . . O X X O . . O O O O O |
$$ | . . X O O . . . O X . O . X . X O X X |
$$ | . . X X O . . . O X . . X . . X X . . |
$$ | . . . . . . . . . X . . . . . . . X . |
$$ ---------------------------------------[/go]
Black can't save the two stones, the following diagram is horrible for Black:
Click Here To Show Diagram Code
[go]$$Wc horrible for Black
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O X X X . 1 2 X X O . . . . . . |
$$ | . . . O O O . X 3 4 O . O . O X . . . |
$$ | . . O , . . . . 5 6 O . . . O , X O . |
$$ | . . O X . . . X 7 . . . . . . O O . O |
$$ | . . X X . . . . . . . . . . . O X O O |
$$ | . . . . . . . O . . O . . O O X X X O |
$$ | . . . . . . . . . . X O O X X . O X O |
$$ | . . . . . . . . . O O X X . X O . . X |
$$ | . . . X . . . . . , . . . X . X X X . |
$$ | . . . . . . . . . . O X X . X . . . . |
$$ | . . . . . . . . . . X O X . . . O . . |
$$ | . . X . X . . . . . X O . . X . . . . |
$$ | . . . . . . . . O . X O . O O O . . . |
$$ | . . . X O . . . . O X O . X . . . . . |
$$ | . . . X O . . . O X X O . . O O O O O |
$$ | . . X O O . . . O X . O . X . X O X X |
$$ | . . X X O . . . O X . . X . . X X . . |
$$ | . . . . . . . . . X . . . . . . . X . |
$$ ---------------------------------------[/go]
Position #58: White to play.
Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . . . . O X X . . . . |
$$ | . . O . . X . . . . O . . O X . . . . |
$$ | . . . O . . . . X , . . . O . X . . . |
$$ | . . . . . . . . . . X . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . O . O X . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . X O O . . . . . . O . . . . . . . . |
$$ | . X X O . . . . . , . . O . O , O . . |
$$ | . . O X . . . . . X . X . . . . . . . |
$$ | . . X . . . . . . O . . X . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . X . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . , O O O O O O X O . |
$$ | . . . . . O . . O O X X O X X X X X . |
$$ | . . . . . . . . O X X . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Shapes to remember (SDK level)

Posted: Sat Sep 18, 2021 4:32 am
by Farodin
I counted black to be slightly ahead in this position, so white has to do something active.
Click Here To Show Diagram Code
[go]$$Wc Black resists
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . 5 3 4 . . O X X . . . . |
$$ | . . O . . X . 1 2 6 O . . O X . . . . |
$$ | . . . O . . . 7 X , . . . O . X . . . |
$$ | . . . . . . . . . . X . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . O . O X . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . X O O . . . . . . O . . . . . . . . |
$$ | . X X O . . . . . , . . O . O , O . . |
$$ | . . O X . . . . . X . X . . . . . . . |
$$ | . . X . . . . . . O . . X . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . X . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . , O O O O O O X O . |
$$ | . . . . . O . . O O X X O X X X X X . |
$$ | . . . . . . . . O X X . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
I think white should jump in at :w1:, breaking the large knight's move. If black resists with :b2: and so on, black suddenly finds himself with 3 weak groups on the board (top left, top center, right side), while white on the top right looks stable enough to not be a big burden in the upcoming fight.
Click Here To Show Diagram Code
[go]$$Wc Black has to pull back
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 5 X . . . . . . . . O X X . . . . |
$$ | . . O . . X . 1 3 . O . . O X . . . . |
$$ | . . . O . . 4 2 X , . . . O . X . . . |
$$ | . . . . . . . . . . X . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . O . O X . . |
$$ | . . O X . . . . . . . . . . . . . . . |
$$ | . X O O . . . . . . O . . . . . . . . |
$$ | . X X O . . . . . , . . O . O , O . . |
$$ | . . O X . . . . . X . X . . . . . . . |
$$ | . . X . . . . . . O . . X . X . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . X . . . . . . . . . . . . . |
$$ | . . O . . . . . . . . . . . . . O . . |
$$ | . . . O . . . . . , O O O O O O X O . |
$$ | . . . . . O . . O O X X O X X X X X . |
$$ | . . . . . . . . O X X . X . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
So I think black can't resist, and has to pull back at :b2: to connect his stones. White does likewise with :w3:. After this, I think white can even afford to play at :w5: immediately, since the black group is now unsettled. After this sequence the territory balance swings back into white's favour.

Re: Shapes to remember (SDK level)

Posted: Sat Sep 18, 2021 1:03 pm
by jlt
Farodin found the blue move.

Position #59, White to play. From a game I played in my club. How to respond to the last move?
Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . X . . . . . . . . . . X . . . . |
$$ | . . X . X O . . . . . . O X . . . . . |
$$ | . . X X O X O . . . . O . O X X X . . |
$$ | . . O O O . . . . , . . . O X O O . . |
$$ | . . . . . . . . . . . . . X O . . . . |
$$ | . . . . . . . . . . . . . . O . B . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . . . . . . . O O . . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . , . . . . . , . . . . . X O O . |
$$ | . . . X . . . . . . . . . X . . X O . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Answer:
Do not connect passively at Q15!
Click Here To Show Diagram Code
[go]$$Wc Answer
$$ ---------------------------------------
$$ | . . . X . . . . . . . . . . X . . . . |
$$ | . . X . X O . . . . . . O X . . . 2 . |
$$ | . . X X O X O . . . . O . O X X X 1 . |
$$ | . . O O O . . . . , . . . O X O O 3 . |
$$ | . . . . . . . . . . . . . X O . . . . |
$$ | . . . . . . . . . . . . . . O . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . . . . . . . O O . . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . , . . . . . , . . . . . X O O . |
$$ | . . . X . . . . . . . . . X . . X O . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Later if Black wants to pull out the peeping stone, the local continuation looks like this
Click Here To Show Diagram Code
[go]$$Wc Continuation
$$ ---------------------------------------
$$ | . . . X . . . . . . . . . . X . . 6 . |
$$ | . . X . X O . . . . . . O X . a . X 5 |
$$ | . . X X O X O . . . . O . O X X X O . |
$$ | . . O O O . . . . , . . . O X O O O . |
$$ | . . . . . . . . . . . . . X O . . . . |
$$ | . . . . . . . . . . . . . . O 7 X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . 4 . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]
Black will probably need to add a move at "a" later.

If instead of :b4: Black lives in the corner immediately, a local continuation like this may be played.
Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . X . . . . . . . . . . X . . . . |
$$ | . . X . X O . . . . . . O X . . . X 4 |
$$ | . . X X O X O . . . . O . O X X X O . |
$$ | . . O O O . . . . , . . . O X O O O . |
$$ | . . . . . . . . . . . . . X O . . . . |
$$ | . . . . . . . . . . . . . . O . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . 5 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

Re: Shapes to remember (SDK level)

Posted: Mon Jan 03, 2022 6:04 am
by jlt
Position #60, Black to play. A rather basic shape, how could I miss it?
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . O O X X . . , . . . |
$$ | . . . . . . . . O . X O X . . . . . . |
$$ | . . . . . . . X O . X O . . . . . . . |
$$ | . . . . . . . . X . X . O . X . . . . |
$$ | . X . . . . . . . . . . . O O X X . . |
$$ | . . . O . . . . O . X . O . . O X . . |
$$ | . . X O . . . . . , . . . . . O X . . |
$$ | . . X O . . . . O . X . O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Shapes to remember (SDK level)

Posted: Mon Jan 03, 2022 7:47 am
by dhu163
J6 prevents the double peep and helps H7 while damaging J5. W does have aji to cut through imminently with K5 L6 L4, but if required, B even has M7 in half sente (damaging the right), but allowing a locally efficient connection with M5 bamboo.

Re: Shapes to remember (SDK level)

Posted: Mon Jan 03, 2022 9:09 am
by Knotwilg
Read the same as dhu and now wondering about this:
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . O O X X . . , . . . |
$$ | . . . . . . . . O . X O X . . . . . . |
$$ | . . . . . . . X O . X O . . . . . . . |
$$ | . . . . . . . . X . X . O . X . . . . |
$$ | . X . . . . . . X . X . . O O X X . . |
$$ | . . . O . . . . O O X 2 O . 7 O X . . |
$$ | . . X O . . . . . O O X 5 6 8 O X . . |
$$ | . . X O . . . . O . X 1 O 9 O X . . . |
$$ | . . . . . . . . . . . . 3 4 O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
but indeed, Hu's suggestion may be best
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . O O X X . . , . . . |
$$ | . . . . . . . . O . X W X . . . . . . |
$$ | . . . . . . . X O . X W a . . . . . . |
$$ | . . . . . . . . X . X 3 O . X . . . . |
$$ | . X . . . . . . 1 . . . . O O X X . . |
$$ | . . . O . . . . O 2 X b O . . O X . . |
$$ | . . X O . . . . . , . . . . . O X . . |
$$ | . . X O . . . . O . X . O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Allowing the capture at A is probably too much to bear
An amusing after thought with KataGo:
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . 1 . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . O O X X . . , . . . |
$$ | . . . . . . . . O . X W X . . . . . . |
$$ | . . . . . . . X O 6 X W . . . . . . . |
$$ | . . . . . . . 3 X 4 X . O . X . . . . |
$$ | . X . . . . . . 2 5 . . . O O X X . . |
$$ | . . . O . . . . O . X . O . . O X . . |
$$ | . . X O . . . . . , . . . . . O X . . |
$$ | . . X O . . . . O . X . O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Where to play now as Black? I don't know if the tesuji has a name :)

Re: Shapes to remember (SDK level)

Posted: Mon Jan 03, 2022 9:59 am
by jlt
Thanks for your remarks, you indeed found the same first move as Katago:
Click Here To Show Diagram Code
[go]$$Bc
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . W W X X . . , . . . |
$$ | . . . . . . . . W . X O X . . . . . . |
$$ | . . . . . . . X W . X O . . . . . . . |
$$ | . . . . . . . a X . X . O . X . . . . |
$$ | . X . . . . 3 . 1 . . . . O O X X . . |
$$ | . . . W . . . 2 O . X . O . . O X . . |
$$ | . . X W . . . . . , . . . . . O X . . |
$$ | . . X W . . . . O . B . O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
(If :w2: is at a then :b3: is at :w2: making miai of capturing one stone or another.)

Katago doesn't seem to care much about the marked black stone. I don't understand its variations as they are rather complicated but it seems it wants to make a strong central group in order to attack either marked white group. Here is for instance a simple variation which is considered as good for Black:
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . O O X X . . , . . . |
$$ | . . . . . . . . O . X O X . . . . . . |
$$ | . . . . . . . X O . X O . . . . . . . |
$$ | . . . . . . . . X . X . O . X . . . . |
$$ | . X . . . . . . 1 3 . . . O O X X . . |
$$ | . . . O . . . 9 O 2 X 7 O . . O X . . |
$$ | . . X O . . . . . 6 4 5 . . . O X . . |
$$ | . . X O . . . . O . X 8 O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
however H5 seems to be a vital point that Katago wants to play at almost every move.

Re: Shapes to remember (SDK level)

Posted: Mon Jan 03, 2022 10:09 am
by jlt
P.S. For your last question, I thought about this tesuji but I am not sure it works.
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . O . . . O . . . . . O . . . . . |
$$ | . . . , O . . . . , . . . . . X . . . |
$$ | . . X . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . X . . . . . . . . 1 . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . 7 O O X X . . , . . . |
$$ | . . . . . . . . O . X W X . . . . . . |
$$ | . . . . . . . X O 6 X W . . . . . . . |
$$ | . . . . . . . 3 X 4 X . O . X . . . . |
$$ | . X . . . . . . 2 5 . . . O O X X . . |
$$ | . . . O . . . . O . X . O . . O X . . |
$$ | . . X O . . . . . , . . . . . O X . . |
$$ | . . X O . . . . O . X . O . O X . . . |
$$ | . . . . . . . . . . . . . . O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
https://senseis.xmp.net/?AngleWedge

Re: Shapes to remember (SDK level)

Posted: Mon Jan 17, 2022 4:06 am
by jlt
Position #61, Balck to play. Again a rather basic shape.
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X O . O X . . O . . . . . . X . . . |
$$ | . . X O . X . X O , . O . . X , . . . |
$$ | . . X O . . . . X . . . . . . . O . . |
$$ | . . X O O . . X . . . . . . . . . . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . . O . . . . . . . . O . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . O . . . |
$$ | . . . X . . . . . O . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Shapes to remember (SDK level)

Posted: Mon Jan 17, 2022 5:17 am
by Knotwilg
Hane at the head of two, I assume. BTW before counting the stones I assumed from the shape it was White's turn to play and I would also play there.
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X O . O X . 1 O . . . . . . X . . . |
$$ | . . X O . X . X O , . O . . X , . . . |
$$ | . . X O . . . . X . . . . . . . O . . |
$$ | . . X O O . . X . . . . . . . . . . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . . O . . . . . . . . O . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . O . . . |
$$ | . . . X . . . . . O . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Click Here To Show Diagram Code
[go]$$Bc Alternative
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X O . O X . 2 O . . . . . . X . . . |
$$ | . . X O . X . X O , . O . . X , . . . |
$$ | . . X O . . 4 . X . . . . . . . O . . |
$$ | . . X O O . . X . . . . . . . 1 3 . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . . O . . . . . . . . O . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . O . . . |
$$ | . . . X . . . . . O . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Re: Shapes to remember (SDK level)

Posted: Mon Jan 17, 2022 5:25 am
by jlt
Correct!
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X O . O X . 1 O . a . . . . X . . . |
$$ | . . X O . X . X O , . O . . X , . . . |
$$ | . . X O . . . . X . . . . . . . O . . |
$$ | . . X O O . . X . . . . . . . . . . . |
$$ | . . . X O . . . . . . . . . . . . . . |
$$ | . . . X O . . O . . . . . . . . O . . |
$$ | . . . X . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |[/go]
This is a good point for both, since it strengthens Black and weakens White at the same time. In addition, Black threatens to play at "a".

Re: Shapes to remember (SDK level)

Posted: Sat Feb 12, 2022 1:43 am
by jlt
Position #62, Black to play. White just played this move:
Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . O O O . . |
$$ | . . . . . . . . . . . . . O X O X X . |
$$ | . . . O . O . . . , . . . . X X . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . W . . . . . . . . . . . . . . |
$$ | . . O , X . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . X X . . . . . . . . . . . O X . . |
$$ | . . O , O . . . . , . . . . . , X . . |
$$ | . . . O . . . . . . . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Black has at least two good responses. In the game I played
D11
which is approved by Katago, but I didn't get the continuation right. So how should Black continue after this?

Possible answer:
Katago considers only one move:
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . O O O . . |
$$ | . . . . . . . . . . . . . O X O X X . |
$$ | . . . O . O . . . , . . . . X X . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . d 1 X O . . . . . . . . . . . . . . |
$$ | . a O O X . . . . , . . . . . , . . . |
$$ | . . . . b . . . . . . . . . . . . . . |
$$ | . . X c . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . X X . . . . . . . . . . . O X . . |
$$ | . . O , O . . . . , . . . . . , X . . |
$$ | . . . O . . . . . . . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
This moves threatens the hane "a", so White will have to defend. Before playing "d", White can play at "b" or "c". Let's for instance examine "b".
Click Here To Show Diagram Code
[go]$$Bc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . O O O . . |
$$ | . . . . . . . . . . . . . O X O X X . |
$$ | . . . O . O . . . , . . . . X X . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . 5 9 . 8 . . . . . . . . . . . . . . |
$$ | . 4 1 X O . . . . . . . . . . . . . . |
$$ | . 6 O O X 3 . . . , . . . . . , . . . |
$$ | . . . . 2 7 . . . . . . . . . . . . . |
$$ | . . X 0 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . X X . . . . . . . . . . . O X . . |
$$ | . . O , O . . . . , . . . . . , X . . |
$$ | . . . O . . . . . . . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
Click Here To Show Diagram Code
[go]$$Bcm11
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . O O O . . |
$$ | . . . . . . . . . . . . . O X O X X . |
$$ | . . . O . O . . . , . . . . X X . . . |
$$ | . . O . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X X . O . . . . . . . . . . . . . . |
$$ | . O X X O . . . . . . . . . . . . . . |
$$ | . O O O X X . . . , . . . . . , . . . |
$$ | . . . . O X . . . . . . . . . . . . . |
$$ | . . B O . . . . . . . . . . . . . . . |
$$ | . . 2 . 1 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O O . . |
$$ | . . X X . . . . . . . . . . . O X . . |
$$ | . . O , O . . . . , . . . . . , X . . |
$$ | . . . O . . . . . . . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
The idea being to sacrifice the marked stone, enclose White in sente and get the influence. Black is cut into two pieces but can manage the fight.

Re: Shapes to remember (SDK level)

Posted: Tue Feb 22, 2022 2:36 pm
by jlt
Position #63, White to play in the lower left quadrant. At least two good moves are possible.
Click Here To Show Diagram Code
[go]$$Wc White to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . X . . . . . |
$$ | . . . O . . . . . , . . . . . , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . O . O . O . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . O O . . |
$$ | . . . , X X X . . , . . . . . , X . . |
$$ | . . . O O . O O . . . . . X . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]
All times are UTC-07:00
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