# Tagged Questions

**9**

votes

**1**answer

314 views

### Lower bounds for $|A+A|$ if $A$ contains only perfect squares

Let $A$ a set with $|A|=n$ that contains only perfect squares of integers.
What lower bounds can we give for $|A+A|$?
I think the lower bound $\gg \frac{n^2}{\sqrt{log \,n}}$ holds (this would be ...

**4**

votes

**1**answer

334 views

### A problem related with 'Postage stamp problem'

A friend of mine taught me this question. I found that it is related with 'Postage stamp problem' (though it does not seem to be same).
Let $m,a_1\lt a_2\lt \cdots\lt a_n$ be natural numbers. Now let ...

**1**

vote

**1**answer

143 views

### unique sums in a finite direct product of sets of integers

I am an algebraist, and I am wondering if there is a definition for the following:
Let $A_1$, $A_2$, $\ldots, A_n$ be sets of integers (or more generally, subsets of a group $G$). Say that (for the ...

**8**

votes

**0**answers

483 views

### Cliques in the Paley graph and a problem of Sarkozy

The following question is motivated by pure curiosity; it is not a part
of any research project and I do not have any applications. The question
comes as an interpolation between two notoriously ...