August 2003
<<July August September>>
Solution:
Part 1:
The setup
K . N B N B N B . . . . . . . . K . K . K . K . . . . . . . . . K . K . K . K . . . . . . . . . N . N B N B N B . R . . . . . .
has value = 1/8 + 6/14 + 7/32 + 9/16 = 299/224 = 1.3348
Part 2:
The setup
N B . . . B B . . . . R . . . . . . R . . . . . B N . . . . B . N . . . . . N . . . . . . . . R . . . . R . . . B B . . . N B .
has value = 4/8 + 8/14 + 5/32 = 275/224 = 1.2277...
Naturally, our solutions do not use queens
Several readers said they have proven optimality, either with an exhaustive search, or by using integer programming.
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