Shapes related to the carpenter's square
Keywords: Life & Death
Table of contents |
Shape 1
No outside liberties
is a mistake. The result is one eye to none, Black cannot approach and loses the capturing race.
cannot kill, the result is a seki. The reader may verify that
at a does not work either.
With outside liberties
Shape 2
No outside liberties
If makes an eye here, then
is atari, which allows White to destroy the eye at the corner.
With outside liberties
clamping at the 1-2 point is the tesuji that allows White to kill by a ko. If
at a, the
at b is also a ko.
Shape 3
With an open side
With no outside liberties on the 4th-line L group, W can kill without needing a descent to the second line.
Carpenter's Square with an extra leg
See also: