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The sharp constant in random triangle removal
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Category:Combinatorics Lean version:YES! ✔
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The sharp terminal leave in random triangle removal. Starting from the complete graph on n vertices, repeatedly delete a uniformly chosen remaining triangle. The terminal edge count is asymptotic to $n^{3/2}/(2\sqrt2)$, with mean-square convergence after normalization by n3/2. This proves the triangle case of the Joos–Kühn sharp-constant conjecture.

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released 2026-09-25  |  1 theorem · 7 lemmas · 12 proofs · 10,810 words  |  PLAY LEVEL 1 »  (pdf)
Starting from the complete graph on n vertices, repeatedly remove the three edges of a uniformly chosen remaining triangle. We prove that the number of edges left at termination, divided by n3/2, converges in L2 to $1/(2\sqrt2)$. This proves the triangle case of the sharp-constant conjecture of Joos and Kühn. In particular, the same limit holds in probability and for the normalized expectation.

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