Proposition 6.4.1: The score due to the algorithm is: 2/3 * (Kd - 2)
+ 2
<<
Quite like case 4 of class 5, also case 4 of class 6 has to be
corrected and due to differing strategies (after Black's simplifying
start to connect a ko) is better split into two cases. The
propositions remain the same:
Case 4A: D EVEN && 0 < Td <= D/2
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Case 4B: D EVEN && -D/2 < Td <= 0
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