Skip to content

Erdős problem 26

Let ANA\subset\mathbb{N} be infinite. Must there exist some k1k\geq 1 such that almost all integers have a divisor of the form a+ka+k for some aAa\in A? The question as posed follows negatively from Davenport–Erdős (1951). The AI result settles Tenenbaum's harder variant, also negatively: there is an infinite AA such that for every k1k\geq 1 the set of multiples of A+kA+k has upper density below 0.340.34.

Sources

Browse retained paths and inspect the exact material available for this Problem.

11 retained statements2415f78e850a

Open selected source

Retained excerpts/

VibeMathed

Retained source excerpt1 of 1

Let $A\subset\mathbb{N}$ be infinite. Must there exist some $k\geq 1$ such that almost all integers have a divisor of the form $a+k$ for some $a\in A$? The question as posed follows negatively from Davenport–Erdős (1951). The AI result settles Tenenbaum's harder variant, also negatively: there is an infinite $A$ such that for every $k\geq 1$ the set of multiples of $A+k$ has upper density below $0.34$.

Open exact source location

Search problems.science

Find a Problem, Result, source, or page