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Probabilistic methods prove existence results in a nonconstructive fashion, by showing the chance of randomly selecting a solution is greater than zero.

6 votes

Domination problem with sets

Clearly we can assume that each element in $M$ appears in exactly $4$ subsets. Let $|M| =n$. Stage 1. Take maximal subfamily $\mathcal{A} \subseteq \{S_1,....,S_k\} =:\mathcal{S} $ such that: $\bul …
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