We determine the maximum number of copies of $K_{s, s}$ in a $C_{2 s + 2}$ -free $n$ -vertex graph for all integers $s \geq 2$ and sufficiently large $n$ . Moreover, for $s \in {2, 3}$ and any integer $n$ , we obtain the maximum number of cycles of length $2 s$ in an $n$ -vertex $C_{2 s + 2}$ -free bipartite graph.

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Volume109, Issue2

June 2025

Pages 218-225

Exact Results for Generalized Extremal Problems Forbidding an Even Cycle

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Exact Results for Generalized Extremal Problems Forbidding an Even Cycle

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Open Research

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