Joachim's Ko-Semeai - Putting the Cart
Before the Horse (2013 - 2015)
12c - White Creates Another Ko-Shape
in the Centre
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In many cases, Michael Redmond's kikashi of |
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White's group has five liberties (w, 2 * c, j, m), Black's group has seven liberties (2 * c, b, 2 * k, j, m). This is the "usual" relationship of liberties with Joachim's Ko-Semeai, but we can assume that the shared double-ko in the centre will benefit White. |
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There is nothing that Black could to with the shared double-ko of |
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Therefore, Black will play the sagari of |
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After the changed preparatory sequence, White's group has five liberties (2 * w, 2 * c, j), Black's group has seven liberties (2 * c, b, 2 * k, j, m). This is the "usual" relationship of liberties with Joachim's Ko-Semeai, but we can assume that the double-ko with his group (in the centre, and on the upper edge) will benefit Black. |
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After the changed preparatory sequence, White's group has five liberties (w, 2 * c, j, m), Black's group has only six liberties (2 * c, b, k, j, m). Despite the various ko-shapes, Black seems to have lost a decisive liberty. |
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Continuing with occupying liberties, with a move at |
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White's group has five liberties (2 * w, 2 * c, m), Black's group has only six liberties (2 * c, 2 * b, k, m) again. |
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Black's suicidal ko-threat at |
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White's group has five liberties (2 * w, 3 * c), Black's group has seven liberties (3 * c, 2 * b, k, m). |
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We added the beginning |
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White's group has five liberties (2 * w, 2 * c, j), Black's group has seven liberties (2 * c, 2 * b, k, j, m). |
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If Black throws-in at We will show here that it is now much too late for Black to build a larger eye in the centre. At the end of this preparatory sequence, White's centre group still has an outside liberty left. Therefore, we will shift |
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White's group has five liberties (2 * w, 3 * c), Black's group has seven liberties (3 * c, 3 * b, k). This is the "usual" relationship of liberties with Joachim's Ko-Semeai, so White will win the fight. However - seen overall - it might be advisable for White to not play her kikashi of |

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, I apparently forgot about one important fact: Black will not get both the move at
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in the centre.
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in the bamboo joint will not have been played, too. We will take it off the board, in order to make the following sequences more comprehensible.
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, which works in White's favour. Therefore, White will win the game with ease.
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, so giving atari on White's group.
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instead, will not work either. White will connect the ko at
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of the Nakade Sequence to make this ko-threat more comprehensible.


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