Wiki
Wiki

Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

Updated


Fix f∈Z[X]∖{0}f\in\mathbb Z[X]\setminus\{0\} and ε0∈(0,1/100)\varepsilon_0\in(0,1/100). Let C0C_0 be the constant from Lemma 2.2 of the paper, which depends only on ff: for every prime pp and every interval J⊂[1,p)J\subset[1,p) with ∣J∣≥1|J|\geq1, at most C0∣J∣2/3C_0|J|^{2/3} integers n∈Jn\in J satisfy p∣n!+f(n)p\mid n!+f(n). The paper's OO-constants may depend on ff and ε0\varepsilon_0, but not on xx.

Statement

Suppose that xx is sufficiently large in terms of ff and ε0\varepsilon_0. Let pp be prime, and let tt be an integer satisfying

(10ε0)100≤t≤C0x2/3.\left(\frac{10}{\varepsilon_0}\right)^{100} \leq t\leq C_0x^{2/3}.

Let JJ be an interval with

J⊂[ε0x,min⁡{x,p}),J\subset[\varepsilon_0x,\min\{x,p\}),

and let n1,…,ntn_1,\ldots,n_t be distinct integers in JJ. Then

(log⁡p)∑t′=⌈1+ε02t⌉tmin⁡1≤j≤t′ord⁡p(nj!+f(nj))≤∣J∣2log⁡t+xlog⁡xt0.98+O(x).(2.14)(\log p) \sum_{t'=\left\lceil\frac{1+\varepsilon_0}{2}t\right\rceil}^{t} \min_{1\leq j\leq t'} \operatorname{ord}_p(n_j!+f(n_j)) \leq \frac{|J|}{2}\log t+ \frac{x\log x}{t^{0.98}}+O(x). \tag{2.14}

Source and proof pointer

This is Lemma 2.7 and equation (2.14) on physical p. 6 of the selected arXiv:2103.14894v1 PDF. Its proof occupies physical pp. 7--8 and ends immediately before Section 3.

The source proof uses Definition 2.3, Lemma 2.4, Heath-Brown's prime-gap bound as Lemma 2.5, and Corollary 2.6. Those steps are not transcribed here. This page records the exact statement and dependency pointer only, with no complete-proof or independent-verification claim.

Bears on

No Erdős problem page directly. It is the new input to the proof of Theorem 1.1, whose page states that theorem's relation to Problem 977.