:: Igo Hatsuyôron 120 (2026)

The Non-Main-Semeai Solutions

After the Completion of the Hanezeki

Starting Point = White E15 (after Q17)

White E15 as Move #74 (3 Jigo)

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .

Within the Crosscut-Sequence, the forcing exchange in the left centre / at the bottom has not yet been played (which is a matter of CHITOOM only).

White E15 as Move #76 (4 Jigo)

In the upper right corner, the first exchange of a Q17-reduction of White's territory has already been played.

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .

Within the Crosscut-Sequence, the forcing exchange in the left centre / at the bottom has not yet been played (which is a matter of CHITOOM only).

White E15 as Move #78 (4 Jigo)

In the upper right corner, the first two exchanges of a Q17-reduction of White's territory have already been played.

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .

Within the Crosscut-Sequence, the forcing exchange in the left centre / at the bottom has not yet been played (which is a matter of CHITOOM only).

White E15 as Move #78 (#2) (1 Jigo)

In the upper right corner, the Q17-Reduction-Sequence of White's territory has already been completed.

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .

Black did without both forcing exchanges in the left centre / at the bottom (which is a matter of CHITOOM only).

White E15 as Move #80 (10 Jigo)

In the upper right corner, the Q17-Reduction-Sequence of White's territory has already been completed.

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .

Within the Crosscut-Sequence, the forcing exchange in the left centre / at the bottom has not yet been played (which is a matter of CHITOOM only).

White E15 as Move #82 (1 Jigo)

In the upper right corner, the Q17-Reduction-Sequence of White's territory has already been completed.

Instead of following Black with for a Guzumi-Exchange, White pushes into Black's upper left corner with .



The Jûrokubango has come to an end.

Over the course of the Jûrokubango (bold section), Black's Initial Self-Play Success Ratio (the blue line in the diagram) finally stabilised in the "green" range between 45% and 50%.

We are looking at a viable solution here !

Recently, however, Black's Success Ratio has fallen sharply, so we will probably have to wait and see how things develop in the further course of the self-play training.

28b's surplus of won games in the Jûrokubango (the red line in the diagram) has reached the range of 0 to -5 (showing an upward trend).

28b has therefore mastered this variation just as well as 40b.



Please click the board for SGF-download ...
(28b = Black)

Please click the board for SGF-download ...
(28b = White)

The comments indicate the number of games in which the respective variation was selected.
E.g. "A=19 // B=264" == Variation "A" was played in 19 games, variation "B" in 264 games.
(The labelling is designed for SGF-editors that label next moves with capitals "A", "B", "C", ...)

Copyright © 2026 Thomas Redecker.

Design by Jan van Rongen, modified by Thomas Redecker.

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