:: Igo Hatsuyôron 120 (2021)

Variations of Our Solution (IIIb)

Tricking KataGo (Triple-Ko)

VAR (C) (A) (.1)

: ( 222jd)
White connects her five stones in the upper left that were in atari.
Please note that this move creates an additional approach-move liberty in the upper left corner for her left hand group, and so does not lose a tempo in the Main Semeai.

:
Black takes his chance to play guzumi at the right.

:
Black gives atari at White's two stones in the lower left.

He is still par with the Punishment Semeai Liberty Level, and so is unable to occupy the large endgame point of , defending his lower left corner.

:
White starts the endgame "early".

She might simplify the issue by connecting at in the upper right first.

: ( A 222jf)
Black captures White's two stones in the lower left.

However, he would gain in the Semeai Variation, if he connected at , instead, taking profit outside the Main Semeai area. The overall result of the game would remain unaffected.

: ( 119 222jg ;  A 222ji)
White simplifies the matter by forcing in the left centre in the "classical" way.

She might consider playing the wedge at in the left centre, or connecting her stone in the upper right with a move at , instead.
Both alternative approaches will gain in the alternative Main Variation, compared to Black's best play below.

:
White plays hane at the upper edge.
Taking profit outside the Main Semeai area will benefit her in the Semeai Variation.

: ( A 222jj)
Black defends his territory in the left centre.

However, he would be better in the Capture Variation, if he captured White's single stone in the upper right with a move at , instead. The overall result of the game would remain unaffected.

:
White's push in the upper left destroys two points of Black's territory without losing a tempo in the Main Semeai.

She could also have waited with this move until after Black reinforced his weakness.

:
Black must pre-empt White's throw-in at this point.

:
The Main Semeai continues.

:
Black inserts his kikashi in the hanezeki, because White's scores in both Main Variations will be the same.

Black plays 1/2 reductions.

Before the end of the game, Black will have to connect at in the upper left corner.

Capture Variation:

Compared to the superordinate variation ...

  • White destroyed two points of Black's territory in the upper left.
  • Black's cumulated gain in the upper right corner is eight points.
  • White captured Black's stone at the lower edge, so gaining two points.
  • White got an additional point of territory in the centre.

In total, White lost three points.

White + 6 => White + 3

Semeai Variation:

Compared to the superordinate variation ...

  • White destroyed two points of Black's territory in the upper left.
  • Black destroyed four points of White's territory in the upper right corner.
  • White captured Black's stone at the lower edge, so gaining two points.
  • White captured an additional three Black stones in the upper right, so gaining five points.
  • Black captured an additional White stone in the upper left, so gaining two points.

In total, White gained three points.

Jigo => White + 3

Copyright © 2021 Thomas Redecker.

Design by Jan van Rongen, modified by Thomas Redecker.

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