Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 168142

Questions on the subject additive combinatorics, also known as arithmetic combinatorics, such as questions on: additive bases, sum sets, inverse sum set theorems, sets with small doubling, Sidon sets, Szemerédi's theorem and its ramifications, Gowers uniformity norms, etc. Often combined with the top-level tags nt.number-theory or co.combinatorics. Some additional tags are available for further specialization, including the tags sumsets and sidon-sets.

2 votes
1 answer
396 views

Sets with certain property concerning density of sumsets

I am working with subsets of $[n]$ of the form $(A+B)\cap A$, where $A+B$ is a sumset. Namely, I am interested if there are nonempty sets $B$ such that whenever $A$ covers a positive proportion of $[n …
9 votes
1 answer
256 views

Arithmetic progressions in inverse image of totient function

I noticed on the OEIS that there are various sequences (e.g. A050515-A050520) that describe arithmetic progressions whose totients are all equal. For example, we have $$\varphi(\{1,2\}) = 1$$ $$\varph …
7 votes
1 answer
263 views

Analogue to Szemerédi's theorem for non-monotone sequences

Szemerédi's theorem states that a strictly increasing sequence of positive integers $a_0, a_1, \ldots$ whose range has positive density contains arbitrarily long arithmetic progressions (as subsequenc …
2 votes
Accepted

Analogue to Szemerédi's theorem for non-monotone sequences

It appears the statement is false. The paper "On permutations containing no long arithmetic progressions," by Davis, Entringer, Graham, and Simmons [Acta Arithmetica 34 (1977)] exhibits a permutation …
Marcel K. Goh's user avatar
10 votes
2 answers
921 views

Converse to Erdős' conjecture on arithmetic progressions

I apologise in advance if this has been asked here before. I did a search and did not find anything obvious. Erdős' conjecture states that if $A\subseteq {\bf N}$ is such that $\sum_{n\in A} n^{-1}$ d …