Hello everyone! I'm new to the game and to the forum actually, so, my abject apologies if my topic is in the wrong section.
The answer to the question I'm just about to ask may be right over my head, but I'd still like you to shed some light on the following: Why didn't White capture the group of black stones by playing n8 at his 70th move?
If Black plays at S2 instead of White, then the White group will die. If White plays at P1, then Black plays at R1, if White plays at R1, then Black plays at P1.
Re: White not capturing the group
Posted: Mon May 14, 2012 8:54 am
by blade90
Just as hyperpape said if Black plays S2 the white group will die. I will go into more detail here:
If white captures at 1 he will get 5 stones (10 points). But Black will kill the white group (marked), that are 9 stones + a few points in the corner. It's about double the value of white 1. For that reason capturing with 1 is too small (taking 10 points by giving your opponent 20+ points).
$$W Move 70 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . . . . . . . . O . . O . . X . . | $$ | . . . O . O . . . , . . . . . X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . X , . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . O O X . . | $$ | . . . . . . . . . . . . 1 O T T O . . | $$ | . . . . . . . . . . . O T T T O . X . | $$ | . . O . . . . . . . . . O O O O . . . | $$ | . . . . . . . . . O . O O X X X X X . | $$ | . . . O . . . . . , . X X W W W X . . | $$ | . . O . . X . X X O . X . X W . W X . | $$ | . . . X . . . . . X . . X W W W W 2 . | $$ | . . . . . . . . . . . . . X 3 . 4 . . | $$ ---------------------------------------
[go]$$W Move 70 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . . . . . . . . O . . O . . X . . | $$ | . . . O . O . . . , . . . . . X . . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . X X . . . . . . . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . X O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . X . . . | $$ | . . X , . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . O O X . . | $$ | . . . . . . . . . . . . 1 O T T O . . | $$ | . . . . . . . . . . . O T T T O . X . | $$ | . . O . . . . . . . . . O O O O . . . | $$ | . . . . . . . . . O . O O X X X X X . | $$ | . . . O . . . . . , . X X W W W X . . | $$ | . . O . . X . X X O . X . X W . W X . | $$ | . . . X . . . . . X . . X W W W W 2 . | $$ | . . . . . . . . . . . . . X 3 . 4 . . | $$ ---------------------------------------[/go]
I hope this answers your question.
Posted: Mon May 14, 2012 11:35 am
by EdLee
blade90, SuprunP,
$$W Move 70 $$ . . . . . . . . . . . . . | $$ . . . . . . . . . X . . . | $$ . . . , . . . . . , X . . | $$ . . . . . . . . O O X . . | $$ . . . . . . 1 O B B O . . | $$ . . . . . O B B B O . X . | $$ . . . . . . O O O O . . . | $$ . . . O . O O X X X X X . | $$ . . . , . X X W W W X . . | $$ . X X O . X . X W . W X . | $$ . . . X . . X W W W W 2 . | $$ . . . . . . . X 3 . 4 . . | $$---------------------------
[go]$$W Move 70 $$ . . . . . . . . . . . . . | $$ . . . . . . . . . X . . . | $$ . . . , . . . . . , X . . | $$ . . . . . . . . O O X . . | $$ . . . . . . 1 O B B O . . | $$ . . . . . O B B B O . X . | $$ . . . . . . O O O O . . . | $$ . . . O . O O X X X X X . | $$ . . . , . X X W W W X . . | $$ . X X O . X . X W . W X . | $$ . . . X . . X W W W W 2 . | $$ . . . . . . . X 3 . 4 . . | $$---------------------------[/go]
blade90 wrote:It's about double the value of white 1.
There's more subtlety. The value of is not only the five stones -- the resulting powerful W shape also has value. Moreover, is sente -- is gote. And blade90 only played and to show SuprunP that is dead -- in reality W would not waste a ko threat by playing immediately after .
is not only the five 
stones -- the resulting powerful W shape also has value.
is gote. And blade90 only played 
and 
to show SuprunP that 
is dead --