Igo Hatsuyo-ron Problem 167 / Attempts

after a ( at , at )  

unkx80: Can be played here?

With a white stone at c it is a snapback. Like this white can't resist.  

tapir: Seems, i totally missed this . I'll try again some day.

after a  

unkx80: Looks like White loses the capturing race by one liberty. The - exchange seems immaterial to the outcome.

after b  

tapir: is threatening to live like in the second diagram. Can white do anything after prevents life on the edge? I stopped my initial attempt here... i tried several points but missed the point. But after trying again, I'm confident that the best black can have after is ko - i marked the underlying pattern, which white wins due to her local threats.

I deleted a lot of failing lines and initial attempts here. I was impressed by the beauty and precision of this tsumego. Every stone is right on its place and every single one is necessarily there.

John F. This is pretty ingenious, and may even be a correct solution the pros have missed (it is Igo Hatsuyoron after all) but the pro solution appears to concentrate on the outside.

Bill: Yes, it is quite a nice line. :) The book solution has no ko, though.

Tapir: I'm very tempted to look after the book solution now... :)