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Difficult abstraction with sets

Source: European Mathematical Cup 2022, Junior Division, Problem 4

December 19, 2022
combinatoricsSetsintersections

Problem Statement

A collection FF of distinct (not necessarily non-empty) subsets of X={1,2,,300}X = \{1,2,\ldots,300\} is lovely if for any three (not necessarily distinct) sets AA, BB and CC in FF at most three out of the following eight sets are non-empty \begin{align*}A \cap B \cap C, \ \ \ \overline{A} \cap B \cap C, \ \ \ A \cap \overline{B} \cap C, \ \ \ A \cap B \cap \overline{C}, \\ \overline{A} \cap \overline{B} \cap C, \ \ \ \overline{A} \cap B \cap \overline {C}, \ \ \ A \cap \overline{B} \cap \overline{C}, \ \ \ \overline{A} \cap \overline{B} \cap \overline{C} \end{align*} where S\overline{S} denotes the set of all elements of XX which are not in SS.
What is the greatest possible number of sets in a lovely collection?