RTG Problem 66 / Attempts

White first, W ko  

hhw: If White first, she can play at and get a ko at with a after .

Black first, W ko  

hhw: If Black first and he protects against the previous path with , White can still get the ko at starting with .

Not cautious enough  

tderz: 'Sakata' on GoDiscussions suggested here, justifying it with the addidional advantage of being 'bigger' ( as are in atari it would even be 'sente').

However, White remains vigilant and throws in @W7= with which results in a transposition to the wrong attempt with (only) i) ko (s.b.) or a nakade too big ii):

i)

only ko  

ii)

too big a nakade  

if Black was connecting at A:

too big a nakade  

... this would create a living shape !

Black first. @  

• prevents ko
• threatens to connect
• prevents the connection
• kills the corner
• - remove the eye in the center.

Black first, continued  

After , the best white can get is a rabbity six eyeshape in the corner. And since black ahs an eye in the corner, it can never be seki. White is dead.

hhw: Ah, missed the dead shape. That's what I get for attempting so early in the morning. :)

Herman: White first

White first  

After , it will be ko