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2013 AIME I Question 4

AIME · 2013 AIME I

Question 4

In the array of $13$ squares shown below, $8$ squares are colored red, and the remaining $5$ squares are colored blue. If one of all possible such colorings is chosen at random, the probability that the chosen colored array appears the same when rotated $90^\circ$ around the central square is $\frac{1}{n},$ where $n$ is a positive integer. Find $n.$

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