yaya17 : Black to kill
What about the sequence B-D19, W-B19, B-D18, W-A18 ? White is alive, and so is black. Perhaps the problem should be labeled as 'Black to live' ? Thank you for your attention
Ruknight: This tsumego is incorrect? It says the correct sequence is C19, A18, B19. But, if white plays B19 instead of A18 it becomes a ko again like in the incorrect variation of D18 first move
d4rkm4tter: Yes, so C19 first move is incorrect as it results in ko.
Shouldn't the only correct variation be the one that goes D1 B1 A2 because that is the only variation that kills the opponent?