EVENT
BOARDSIZE 19
SETUP W E17 R16 R15 R4 R6 Q3 P3 B4 C6 C9 
SETUP B C16 P17 Q15 Q14 O3 O4 P4 K3 D4 F4 C3 
MARK 1@Q15 2@R15 3@Q14
COM
Problem 172. White to move.  

After Black 1 and 3, what are White's next two moves ? 
ENDCOM
W 1 R14
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White should crawl once with 1, ...
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  VAR
  W 1 R13
  COM
  Failure.

  Jumping to White 1 is not good.
  ENDCOM
  B 2 R14
  W 3 S14
  B 4 S13
  W 5 S12
  B 6 Q13
  W 7 R12
  B 8 S15
  W 9 T13
  B 10 R17
  COM
  Black will strengthen his position with the forcing moves to
  10, ...
  ENDCOM
  W 11 S16
  B 12 J17
  COM
  ... then pincer with 12.
  ENDCOM
  ENDVAR
B 2 Q13
  VAR
  B 2 J17
  MARK 1@R14
  COM
  Failure for Black.

  If Black ignores White 1 and pincers with 2, ...
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  W 3 Q13
  COM
  ... White will hane with 3.
  ENDCOM
  B 4 P13
  COM
  If Black also hanes at 4, ...
  ENDCOM
  W 5 P12
  MARK 2@J17 \t@Q14 \t@Q15
  COM
  ... White will play a two-step hane at 5 and the right side will
  have become big. In any case, the two marked black stones have
  become bad moves because they have given White profit. If Black
  wants to pincer with 2, he should do so without playing the marked
  stones.
  <=
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  ENDVAR
W 3 K17
COM
... then extend to 3 to neutralise Black's thick wall on the
right.
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B 4 R13
MARK \t@R6
COM
Black 4 is a thick move, but, in this case, White doesn't mind
because her marked stone neutralises this thickness.
ENDCOM
W 5 R18
COM
White next jumps to 5 in order to live in the corner.
<=
ENDCOM