Xuanxuan Qijing Problem 111

[xed_over]

A friend of mine was working his way through Mr Fairbairn's ebook, Gateway to All Marvels, problem 10 (Xuanxuan Qijing Problem 111), and thinks he found a way for black to prevent white from killing, by forcing either a ko or seki.

$$W White to play
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O . . . |
$$ . . . . . O X X . |
$$ . . . . . O . X . |
$$ ------------------

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[go]$$W White to play
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O . . . |
$$ . . . . . O X X . |
$$ . . . . . O . X . |
$$ ------------------[/go]

traditional solution...

$$W 7@2 9@2
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X 6 5 |
$$ . . . . . O 4 3 2 |
$$ . . . . . O X X 1 |
$$ . . . . . O . X 8 |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W 7@2 9@2
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X 6 5 |
$$ . . . . . O 4 3 2 |
$$ . . . . . O X X 1 |
$$ . . . . . O . X 8 |
$$ ------------------[/go]

My friend's possible solution(s)...

$$W white to play
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O . 2 . |
$$ . . . . . O X X 1 |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W white to play
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O . 2 . |
$$ . . . . . O X X 1 |
$$ . . . . . O . X . |
$$ ------------------[/go]

How does white kill now?

(can I not do nested hide tags?)

$$W ko
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X 3 |
$$ . . . . . O X 1 X |
$$ . . . . . O X 2 . |
$$ . . . . . O . X 4 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W ko
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X 3 |
$$ . . . . . O X 1 X |
$$ . . . . . O X 2 . |
$$ . . . . . O . X 4 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------[/go]

$$W seki
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X 2 X |
$$ . . . . . O X . 3 |
$$ . . . . . O 4 X 1 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W seki
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X 2 X |
$$ . . . . . O X . 3 |
$$ . . . . . O 4 X 1 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------[/go]

$$W fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O 1 X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . . |
$$ . . . . . O 1 X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------[/go]

$$W fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X 1 . |
$$ . . . . . O . X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X 1 . |
$$ . . . . . O . X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------[/go]

$$W still fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . 1 |
$$ . . . . . O . X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------

Click Here To Show Diagram Code

[go]$$W still fail
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |
$$ . . . . . . O O O |
$$ . . . . . . O X . |
$$ . . . . . O X . X |
$$ . . . . . O X . 1 |
$$ . . . . . O . X 2 |
$$ . . . . . O X X O |
$$ . . . . . O . X . |
$$ ------------------[/go]

Is the traditional solution wrong? Or are we overlooking something?

[Kirby]

I think your friend is correct. Looks like ko or seki to me.

[ez4u]

This is a known error in the original problem. Go Seigen's Japanese book on the Guanzi Pu lists your friend's alternative as the correct way to play, resulting in ko (volume 1 problem 118 there) . Well spotted!

[tchan001]

The correct solution being ko is also found in the newest English version of XXQJ being "Baduk Classic - The Profound and Mysterious Vol. 2" from BadukTV translated and revised by Cho Hye-yeon and published in 2014 (Problem 110 in this book).

Obviously the traditional solution was the intended solution of the original author who had titled the problem as "Battered rain hat".