Hiding Five Colors
Is it possible to place five each of five colored
coins in a 5x5 grid, such that
each coin cannot "see" any other coins with the same color?
Assume there are 4 inches between each grid point and each coin is 1
inch in diameter. Coins can be "seen" along ANY line of sight, unless
another coin is in the way.
For example, red coins in the top-left and top-right corners
cannot see each
other because there are three other coins directly between them.
However, a green coin in the top-left corner
could see a green coin anywhere in the second row, since nothing
is between them.
Source: Original.
Solution
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