:: Igo Hatsuyôron 120 (2021)

Variations of Our Solution (IIIb)

Tricking KataGo (Triple-Ko)

VAR (C) (A) (.2) (.2)

: ( 222mi)
Black cuts in the top right, capturing White's single stone in order to live.

:
White forces once at the right.

:
White attacks Black's upper left corner.

:
Black's corner territory is too large now to become killed outright.

:
White creates an approach-move ko in the corner, but which she will be unable to win.

:
Black throws-in once at the upper edge.

:
Finally, Black gives atari in the corner.

:
White is unable to win the approach-move ko in the corner, so she utilises Black's shortage of liberties at the upper edge, instead.

: (130 222mk)
Black gives atari in the corner again.

He is unable to connect at , instead.
White will answer with . After having occupied all of Black's approach-move liberties at the upper edge, it will be White, who wins the ko fight in the corner.

:
Black lives in the upper right corner.

:
White takes profit at the upper edge.

:
If follows an amateurish idea of the ensuing endgame on the board.

:
White captures the nakade, sooner or later.

:
We will continue with the sequence at the left, in order to calculate the score.

:
As Black's large group at the right is already alive, White has to capture the tail at the moment, when her five-point nakade is filled with three Black stones.
Please assume White's remaining liberties occupied by Black stones.

Otherwise, Black would connect the hanezeki's tail with , and win the ensuing semeai between White's group at the left and his then connected tail-group.

Contrary to the usual Main Semeai sequence, the points from to will be left unoccupied.
Black will only have to take White's group in the lower right corner off the board.

Capture Variation:

Compared to the superordinate variation ...

  • White captured an additional seven Black stones at the upper edge, so gaining thirteen points.
  • At the left, White destroyed two points of Black's territory.
  • White lost one point in the nakade.
  • In the upper right, White lost five points of territory.
  • Black got an additional three points of territory in the upper right.
  • Black did not need to capture White's stones at the right, so gaining two points.

In total, White gained four points.

White + 4 => White + 8

Copyright © 2021 Thomas Redecker.

Design by Jan van Rongen, modified by Thomas Redecker.

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