What is the minimum number
of knights that can be placed on a
standard 8x8 chess board, so that every
square (including those occupied by
knights) is threatened by a knight and
what is such a configuration?
A square
is threatened if a knight can move to
that square on its next move. A knight
moves two squares in one direction
and one square in another direction
(perpendicular to first direction)
to end up on a square of opposite
color. The move can occur even if
intervening squares are occupied.
Present your answer as an 8x8 grid
with ‘o’ representing an unoccupied
square and ‘N’ representing a square
occupied by a knight.
Hint: the
minimum is less than 16.
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