Claims

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2026_09_29_chao_huang_liu: An arXiv preprint of Chao, Huang and Liu claims the limit of $\mathrm{ex}_r(n,\mathcal F)/n^t$ whenever $k=(r-t)s+t$ with $r>t\ge2$, in closed form depending on the parity of $s$, except for $3$-graphs with even $s$, where it shows for $s\ge4$ that the limit exceeds $1/6$. This answers the problem to first order on that family only.

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