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arXiv · 2505.11105

On the Turán number of the expansion of the $t$-fan

Xin Cheng·Dániel Gerbner·Hilal Hama Karim·Junpeng Zhou
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Abstract

The $t$-fan is the graph on $2t+1$ vertices consisting of $t$ triangles which intersect at exactly one common vertex. For a given graph $F$, the $r$-expansion $F^r$ of $F$ is the $r$-uniform hypergraph obtained from $F$ by adding $r-2$ distinct new vertices to each edge of $F$. We determine the Turán number of the 3-expansion of the $t$-fan for sufficiently large $n$.

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Xin Cheng, Dániel Gerbner, Hilal Hama Karim, Junpeng Zhou. 2025-05-16. On the Turán number of the expansion of the $t$-fan. https://arxiv.org/abs/2505.11105

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