Problem
2014 AIME II Problem 13
Ten adults enter a room, remove their shoes, and toss their shoes into a pile. Later, a child randomly pairs each left shoe with a right shoe without regard to which shoes belong together. The probability that for every positive integer k<5, no collection of k pairs made by the child contains the shoes from exactly k of the adults is \frac{m}{n}, where m and n are relatively prime positive integers. Find m+n.
Leading zeroes must be inputted, so if your answer is 34, then input 034
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