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Subsets Avoiding Complementary Pair Sums

1750AdeptCombinatoricsCounting Principles

Harvard-MIT November Tournament

How many subsets $A$ of $\{1,2,3,4,5,6,7,8,9,10\}$ have the property that no two elements of $A$ sum to $11$?
0 students attempted0% solvedRating 1750

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