Skip to main content

All Questions

2 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
8 votes
0 answers
181 views

Rational points with small denominator in $U(n)$

Fix integers $n,d>0$. (I'm probably thinking about $n\leq 6$ and $d\leq 2000$.) Let $X$ be the set of matrices $A\in U(n)$ such that the entries of $dA$ lie in $\mathbb{Z}[i]$. Is there an ...
Neil Strickland's user avatar
4 votes
0 answers
437 views

A sum of Ramanujan sums

I have the following question about Ramanujan sums. (All vectors and matrices here will be understood to have integer entries.) Let $X_q=\{ (x_1,...,x_R)|1\leq x_i\leq q\} $ and let, for any $R\...
tomos's user avatar
  • 1,381