299.--BISHOPS IN CONVOCATION.

The fourteen bishops may be placed in 256 different ways. But every

bishop must always be placed on one of the sides of the board--that

is, somewhere on a row or file on the extreme edge. The puzzle,

therefore, consists in counting the number of different ways that we

can arrange the fourteen round the edge of the board without attack.

This is not a difficult matter. On a chessboard of n² squares 2n - 2

bishops (the maximum number) may always be placed in 2^n ways without

attacking. On an ordinary chessboard n would be 8; therefore 14

bishops may be placed in 256 different ways. It is rather curious that

the general result should come out in so simple a form.

[Illustration]

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