<problem> black to play and win

MJK · Post by **MJK** » Tue Aug 06, 2013 8:21 pm

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . . . X . | $$ ------------[/go]

Enjoy!

and please hide your solutions.

[edit] Japanese rules, no komi, no prisoners [/edit]

illluck · Post by **illluck** » Tue Aug 06, 2013 10:10 pm

frankie99 · Post by **frankie99** » Tue Aug 06, 2013 10:47 pm

Bill Spight · Post by **Bill Spight** » Tue Aug 06, 2013 10:53 pm

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . 1 . X . | $$ ------------[/go]

prevents a second eye.

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . 1 2 X . | $$ ------------[/go]

prevents seki.

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 5 | $$ | O O O O 3 | $$ | . 1 2 X 4 | $$ ------------[/go]

cannot be at 5 because of damezumari.

Variations:

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 2 | $$ | O O O O 5 | $$ | . 1 3 X 4 | $$ ------------[/go]

After

takes the ko, White has no threat.

So the bottom will remain seki.

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 5 | $$ | O O O O 3 | $$ | . 2 1 X 4 | $$ ------------[/go]

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O X | $$ | O O O O X | $$ | . O . 6 O | $$ ------------[/go]

White wins by 1 pt.

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O 3 | $$ | . 2 1 X 4 | $$ ------------[/go]

Click Here To Show Diagram Code: [go]$$c Black to play and win $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 6 | $$ | O O O O X | $$ | . O . 5 O | $$ ------------[/go]

White wins.

Boidhre · Post by **Boidhre** » Tue Aug 06, 2013 11:09 pm

Maybe

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . . 1 X . | $$ ------------[/go]

Click Here To Show Diagram Code: [go]$$c Seki or a ko White can't win: $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 2 | $$ | O O O O . | $$ | . 3 1 X . | $$ ------------[/go]

Click Here To Show Diagram Code: [go]$$c Left with a dead three space eyespace $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . 3 1 X 2 | $$ ------------[/go]

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

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 2 | $$ | O O O O X | $$ | . O . 1 O | $$ ------------[/go]

So...

Click Here To Show Diagram Code: [go]$$c This seems to work for all the above yet lack the problem of the last diagram. $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O . | $$ | O O O O . | $$ | . 1 . X . | $$ ------------[/go]

Click Here To Show Diagram Code: [go]$$c This is a label for the diagram. $$ ------------ $$ | O X . X . | $$ | O X X X X | $$ | O X O O 3 | $$ | O O O O . | $$ | . 1 . X 2 | $$ ------------[/go]

Etc. It seems to come down to a miai between a dead eye shape for white or a false eye on the right. White doesn't seem to be able to avoid both without accepting a seki.

Splatted · Post by **Splatted** » Wed Aug 07, 2013 5:18 am

MJK · Post by **MJK** » Wed Aug 07, 2013 11:06 am

Maybe too easy for L19ers

Below was the most interesting variation imo.

Life In 19x19

<problem> black to play and win

<problem> black to play and win

Re: <problem> black to play and win

Re: <problem> black to play and win

Re: <problem> black to play and win

Re: <problem> black to play and win

Re: <problem> black to play and win

Re: <problem> black to play and win