Sunday Problem #4

Published 28 Jun 2020 by antti (last edited 3 Sep 2020)

This problem was created by Lee Eodeokdung 1p. He showed to me at the European Go Congress 2017, and it quickly became one of my favourite tsumego.

Black to play.

White 2 is the strongest resistance to Black’s attachment of 1. Following...
...after black 7, White dies in a double ko. This is still better for White than dying unconditionally, as the group will supply infinite ko threats.

Comments (4)

Mikho wrote 3 months, 3 weeks ago:

White dead in what... double ko?

gerryg wrote 3 months, 3 weeks ago:

I'm not sure how difficult this problem is supposed to be. Although it all looks solid with lots of eye space the 1-2 points are deadly. The group is unsettled and the outcome depends on whose turn it is. It's more of a problem when it doesn't come with "problem" hanging over it. In a game (at my level) it's much easier to miss.

e.g, B S19, W R18, B T18 W S17 B T19, tenuki, B R19 = bent 4

B S19, W T19 B T18 leaves one throw-in unprotected

White to play either 1-2 point for life. Playing on the point of symmetry, 1-1, (those proverbs... ) looks like it works too. It's not so much "magic on the first line" as a clove of garlic warding off the vampire waiting to bite your neck :) If I recall correctly when the symmetry is expanded by one row and column (even more tricky to spot if it hasn't got "problem" hanging over it, White needs to put a clove of garlic on 2-2

antti wrote 3 months, 3 weeks ago:

There is a meaning to white’s having 2x2 clumps of stones rather than just sticks of two stones. Although the problem looks simple on the first glance, there is a surprising (and entertaining) layer of depth to it!

antti wrote 3 months, 2 weeks ago:

Solution added.


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