Problem No. 120 from Igo Hatsuyoron
Created by Inoue Dosetsu Inseki (1646 - 1719)

Black to play and win
back to the Introduction


 What this problem is really about.
Explains a very special type of Seki.

 Highlights - our key-results
Highly recommended for a better overview. Provides a historical outline of the key-results of our investigations so far, including our solution.

 Main Path of the "official" solution in detail (contains the strongest White resistance, which wins the game for White).
The sequence with the strongest play of both sides; professionally approved. Includes the key-move found by Joachim Meinhardt, after which White wins the game.

 Table "Main Path" (summary of the variations of the Main Path).

 Table "The second Throw-in" (summary of the results of our investigations).

 Several questions from 2007 (= the path to the Guzumi).
Some questions, which arose in 2007 during the discussions with Joachim while writing and editing these texts, and which finally led to the development of the Guzumi.

 Variations of the Main Path in detail.
Contains most of the variations for the Main Path found in the sources. We added some variations we thought to be helpful for the reader, too.

 Variations after the second Throw-in in detail.
The sources mention a Semeai that will end harmful for Black after this move. We went through the "common" Semeai-variations, but found none.
We had looked for a move that might open the door again for a win by Black. This includes our attempts after my very first idea for a "bad-shape" move in the top right corner. Finally we concluded that the timing for this move was not correct.

 Research on the move that probably solves the problem (i. e. might win the game for Black).
Contains variations (as of 2008) after what we think to be the correct timing for the "bad-shape" move winning Black the game (in our opinion). Most of these variations are on amateur Kyu level; only a few have been checked by professional knowledge.

 TIME - what distinguishes between amateurs and professionals (or joins them together ?).
An essay, based on my experiences with professionals.

Our book on Igo Hatsuyoron 120 can be found at

If you'd like the whole contents on one page, please click here.

The diagram-pictures were created with "SGF conversion" on Jan van der Steen's
Compiled by Thomas Redecker.

For a blog on East-Asian books on Go, please refer to Tchan001's Blog..

(c) DGoB -  letzte Aktualisierung: 2011-10-11 20:00,