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Statement

Setting (p. 20). Factor n=∏j=1Ω(n)pj(n)n=\prod_{j=1}^{\Omega(n)}p_j(n) with p1(n)≥p2(n)≥⋯p_1(n)\ge p_2(n)\ge\cdots, put pj(n)=1p_j(n)=1 for j>Ω(n)j>\Omega(n), and let

S(n)=(log⁡p1(n)log⁡n,log⁡p2(n)log⁡n,…).S(n)=\left(\frac{\log p_1(n)}{\log n},\frac{\log p_2(n)}{\log n},\ldots\right).

Probabilities over a set of integers are natural densities: by footnote 3 (p. 20), for B⊆A⊆N\mathcal B\subseteq\mathcal A\subseteq\mathbb N, P(n∈B∣n∈A)=α\mathbf P(n\in\mathcal B\mid n\in\mathcal A)=\alpha means that ∣{n∈B:n≤x}∣/∣{n∈A:n≤x}∣→α|\{n\in\mathcal B:n\le x\}|/|\{n\in\mathcal A:n\le x\}|\to\alpha. The Poisson--Dirichlet distribution PD(1)PD(1) is the law of the decreasing rearrangement of U1,(1−U1)U2,(1−U1)(1−U2)U3,…U_1,(1-U_1)U_2,(1-U_1)(1-U_2)U_3,\ldots for independent UiU_i uniform on [0,1][0,1] (Donnelly--Grimmett, (6.1)). Over all integers, S(n)S(n) has PD(1)PD(1) distribution in the sense the paper states: for each jj, the first jj components of S(n)S(n) are distributed as the first jj components of PD(1)PD(1) (Billingsley, 1972; p. 20).

Conjecture 5 (p. 20, quoted). "As pp runs over the set of primes, S(p−1)S(p-1) has PD(1)PD(1) distribution."

The paper calls the conjecture widely believed and "a simple consequence of EH" (the Elliott--Halberstam conjecture), without proof (p. 20). It then assumes, beyond Conjecture 5, that the vectors S(q−1)S(q-1) for the primes q∣p−1q\mid p-1 are independent and so on down the Pratt tree, which turns the tree into a random fragmentation process, equivalently a branching random walk, the model behind Conjectures 2 and 3 (pp. 20--21).

Proof pointer

None: a conjecture. The paper cites Lamzouri for a result assuming EH: the largest prime at each fixed level of the Pratt tree has the distribution the model predicts (p. 21).

Read depth

Claims checked: the definitions, footnote 3 and Conjecture 5 were read clause by clause on the print (p. 20). Nothing here is independently reviewed.

Dependencies

None in the corpus.

Source. Kevin Ford, Sergei V. Konyagin and Florian Luca, Prime chains and Pratt trees, Geom. Funct. Anal. 20 (2010), no. 5, 1231--1258, doi:10.1007/s00039-010-0089-0, arXiv:0904.0473; page numbers are those of the arXiv version 4 named on the source card.

Bears on

None among the problems the corpus links to this paper. The 2026 manuscript on the Poisson--Dirichlet law of prime predecessors states that its Theorem 1.1 resolves this conjecture.