>>>>> Michael Hopwood <michael@xxxxxxxxxxx> writes:

 > I'm no chess OR maths expert but - surely they are not actually chess
 > queens if any two of the same colour can threaten each other?  The
 > puzzle using actual chess queens, at least one of which is of the
 > other colour, would look quite different...

	AIUI, for the purposes of this puzzle, /each/ of the queens is
	assumed to be of its own distinct colour.

--cut: http://en.wikipedia.org/wiki/Eight_queens_puzzle --
    The eight queens puzzle is the problem of placing eight chess queens
    on an 8C8 chessboard so that no two queens attack each other.  Thus,
    a solution requires that no two queens share the same row, column,
    or diagonal.  The eight queens puzzle is an example of the more
    general n-queens problem of placing n queens on an nCn chessboard,
    where solutions exist for all natural numbers n with the exception
    of 2 and 3.
--cut: http://en.wikipedia.org/wiki/Eight_queens_puzzle --

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