Life In 19x19

Posted: **Sun Apr 30, 2017 10:20 pm**

Welcome to Round 11 of the L19 Go Problem Championship.

All problems are black to play. As usual, provide your solutions either via hide tags, or direct private message to me.

Problem 1 (3 points)

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

Problem 2 (6 points)

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

Problem 3 (9 points)

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

Have fun!

Posted: **Sun Apr 30, 2017 11:13 pm**

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

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

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

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

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

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

Click Here To Show Diagram Code: [go]$$B W dies $$ ----------------- $$ . . . . X . X . | $$ . X . X O 5 O . | $$ . . X . O . O . | $$ . . . O , O O . | $$ . . X O O O X . | $$ . . X X X X X . | $$ . . . . . . . . |[/go]

Click Here To Show Diagram Code: [go]$$B (a) & (b) seem miai... $$ ----------------- $$ . . . . X . . . | $$ . X . X O X O . | $$ . . X b O 1 a . | $$ . . . O , O O . | $$ . . X O O O X . | $$ . . X X X X X . | $$ . . . . . . . . |[/go]

Click Here To Show Diagram Code: [go]$$B (c) & (d) miai $$ ----------------- $$ . . . . X 5 3 . | $$ . X . X O X O 4 | $$ . . X d O 1 2 . | $$ . . . O , O O c | $$ . . X O O O X . | $$ . . X X X X X . | $$ . . . . . . . . |[/go]

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

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

Posted: **Mon May 01, 2017 2:39 am**

Re: Problem 3

I haven't been participating but I could not resist on this problem

Click Here To Show Diagram Code: [go]$$Bcm1 The tesuji? $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | X X X X . . . . . . . . . . . . . . . | $$ | O 6 2 O X . . . . . . . . . . . . . . | $$ | O 5 . O X . . . . . . . . . . . . . . | $$ | 8 7 4 O X . . . . , . . . . . , . . . | $$ | . O 3 O X . . . . . . . . . . . . . . | $$ | 9 O 1 X . X . . . . . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Wcm10 The rest? 13 @ 11, 15 @ marked stone $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | X X X X . . . . . . . . . . . . . . . | $$ | O O O O X . . . . . . . . . . . . . . | $$ | O X 5 O X . . . . . . . . . . . . . . | $$ | O B O O X . . . . , . . . . . , . . . | $$ | 2 O X O X . . . . . . . . . . . . . . | $$ | X O X X . X . . . . . . . . . . . . . | $$ | 3 1 O X . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Click Here To Show Diagram Code: [go]$$Bc Final position - White is captured in a double snapback $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | X X X X . . . . . . . . . . . . . . . | $$ | O O O O X . . . . . . . . . . . . . . | $$ | O . O O X . . . . . . . . . . . . . . | $$ | O X O O X . . . . , . . . . . , . . . | $$ | X O X O X . . . . . . . . . . . . . . | $$ | . O X X . X . . . . . . . . . . . . . | $$ | O O O X . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

below is also interesting. White tries to create the alternative of an eye in the middle of the board to play/protect the vital point at B5 in sente (in order to live by then connecting at B1). However,

allows Black to play B5. If White tries

,

continues to threaten B5. If White plays "a" instead, Black answers with "b" still threatening B5. If White tries "b" instead, Black plays "a" and can still follow up with B5! Personally I found this more interesting than the tesuji, which I learned from a dull tsumego book.

Click Here To Show Diagram Code: [go]$$Bcm1 Interesting $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | X X X X . . . . . . . . . . . . . . . | $$ | O 4 a O X . . . . . . . . . . . . . . | $$ | O . 5 O X . . . . . . . . . . . . . . | $$ | . 2 b O X . . . . , . . . . . , . . . | $$ | . O 3 O X . . . . . . . . . . . . . . | $$ | . O 1 X . X . . . . . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Needless to say, if Kirby has some other clever resource for White, I was too lazy to find it as usual!

Posted: **Sun May 07, 2017 10:00 pm**

@EdLee:

Posted: **Sun May 07, 2017 10:00 pm**

@ez4u:

Posted: **Sun May 07, 2017 10:04 pm**

Solutions and updated leader board are given below.

Problem 1

Problem 2

Problem 3

Leaderboard

gamesorry - 120
EdLee - 85
dfan - 79
Schachus - 68
Shaddy - 49
hyperpape - 26
mongus - 19
Lanrose - 16
jeromie - 13
ez4u - 9

Life In 19x19

L19 Go Problem Championship: Round 11

L19 Go Problem Championship: Round 11

Re: L19 Go Problem Championship: Round 11

Re: L19 Go Problem Championship: Round 11

Re: L19 Go Problem Championship: Round 11

Re: L19 Go Problem Championship: Round 11