EVENT
BOARDSIZE 19
SETUP W D17 C16 C15 F17 L17 O17 Q18 R10 Q8 R6 S4 D4 C3 C6 
SETUP B Q16 R17 R14 R3 Q4 O4 C8 D10 C14 D14 D15 J3 F3 D2 
MARK \t@Q8
COM
Problem 63. Black to play.  

White has just defended her position on the lower right side.
Where should Black play next ? 
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B 1 C2
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

Most of White's stones are secure, but, if Black crawls to 1,
he threatens White's three stones in the lower left corner. Next
...
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  VAR
  B 1 G15
  COM
  Failure.

  If Black jumps to 1, ...
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  W 2 C2
  MARK A@L3
  COM
  ... White will defend with 2. White is strong on the lower left
  and right, so she can now aim at the invasion of A.
  <=
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  ENDVAR
W 2 F4
COM
... White attaches at 2 and ...
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  VAR
  W 2 B2
  COM
  Failure for White.

  White 2 here ...
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  B 3 B4
  COM
  ... would be answered by Black 3, leaving White without eyes.
  <=
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  ENDVAR
B 3 G4
W 4 F5
B 5 G5
W 6 F7
B 7 G6
W 8 F6
COM
... secures her stones with the sequence to 7. White has gained
no territory, but, ...
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B 9 H8
COM
... when Black plays 8, a large moyo at the bottom is starting
to take shape.
<=
ENDCOM