This also lives.
Dieter: Yes, but with less points. The question concerned the status of the White group if White plays elsewhere.
ilan: The Oracle of ilan answered your original question and will now move on.
Dieter: Maybe someone else wants to try if the group could live without White answering locally.
Grauniad: I don't see how White can live after a Black move at the same point.
prevents ko and makes miai of a and b. This and move
are not obvious to me, and I suspect there may be holes in the reasoning.
Ed?: White is alive here at 'a' or 'b'.
ed?: here threatens to separate the the white stones by pushing through at
. If the exchange of
for
is not sente then black can kill.
White throws in with to make a ko. White will play at either point 'a' to finish the ko.
White is alive here.
White is alive after
If the exchange of for
is not sente for white black can kill.
Black can get a sente seki by exchanging 'a' for 'b'. Playing 'c' instead leaves open the possibility of a ko. White 'b' in response to 'c' leaves a 1000 yr ko, although if white starts it early by throwing in at 'a' it is a direct ko for white but black will need a lot of approach moves. If black can play 'c' and white tenuki's, black 'b' makes it a direct ko.
This diagram seems to be white's best option.
Here white dies. at
would give ko after black pushes through at
.
'a' and 'b' are miai so white must fight the ko
Resisting with is clearly bad, white collapses.
This attack leads to seki. at 'a' would lead to ko. Again white is dead if the exchange of
for
isn't sente.
If at
then white lives with territory at 2.
(Hicham): Isn't 4 atari?
Ed? True white needs to exchange 'a' for 'b' before playing
[alternative: alive --Dieter