EVENT
BOARDSIZE 19
SETUP W C12 C16 E17 H17 R10 Q18 
SETUP B C10 K17 Q17 R15 P17 
MARK 2@P17 1@Q18
COM
Problem 66. White to play.  

White has attacked the small-knight enclosure by attaching at
1. How should White follow up his invasion after Black extends
to 2 ? 
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W 1 R17
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White easily lives in the corner ...
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  VAR
  W 1 P18
  USER
  CORRECT ANSWER
  ENDUSER
  COM
  Correct Answer.

  Living in the corner is small, so White might play 1 ...
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  B 2 R18
  W 3 O17
  COM
  ... and 3.
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  B 4 M17
  COM
  If Black attacks with 4, ...
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  W 5 O15
  MARK C@R17 D@R16 B@R14 A@Q15
  COM
  ... White jumps to 5, aiming to make sabaki by attaching at A.
  If then Black B, White plays C, if Black D, White answers with
  B.
  <=
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  ENDVAR
B 2 R16
W 3 S17
COM
... with 3 ...
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B 4 P18
W 5 R19
COM
... and 5. However, the corner territory is small and White ends
in gote, so the timing in playing these moves is crucial.
<=
ENDCOM