TsumegoFromGames146/Attempts

Ko - black takes first  

Ko - black takes first  

fractic: I don't think the order is right. This is better. White should play before .

Herman: If white plays before , it fails ompletely. tapir's solution is correct, but white should play in the first diagram immediately, rather than first playing .

tapir: Indeed. Visualising with removing stones is difficult for me.

Still ko - black can't help it + white takes first, inferior for black  

Ko - white takes first, inferior result for black  

Ko - black takes first  

Herman: Correct! Note that white can play at a for a sente seki, but that will usually be inferior (if it were superior, white black should play as in diagram 1 and allow that ko (which black takes first).