On Symmetric 3-wise Intersecting Families
نویسندگان
چکیده
A family of sets is said to be symmetric if its automorphism group is transitive, and 3-wise intersecting if any three sets in the family have nonempty intersection. Frankl conjectured in 1981 that if A is a symmetric 3-wise intersecting family of subsets of {1, 2, . . . , n}, then |A| = o(2). Here, we give a short proof of Frankl’s conjecture using a sharp threshold result of Friedgut and Kalai.
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