EVENT
BOARDSIZE 19
SETUP W D17 C16 C15 C14 D4 
SETUP B D15 D16 E17 Q16 Q4 
MARK 1@D15 3@D16 5@E17 2@C15 4@C16 6@C14
COM
Problem 25. Black to play.  

In response to White 2, Black 3 and 5 are large-scale strategic
moves which work well with Black's niren-sei on the right. What
should Black do after White 6 ? 
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B 1 Q10
USER
CORRECT ANSWER
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COM
Correct Answer.

Making a sanren-sei on the side with 1 is strategically an interesting
move.
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W 2 D18
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If White fortifies her corner territory with 2, ...
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B 3 K16
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... Black will take another star point at the top with 3. (See
Get Strong at Joseki 1, Problem 105.)
<=
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