Sungjin Kim's user avatar
Sungjin Kim's user avatar
Sungjin Kim's user avatar
Sungjin Kim
  • Member for 12 years, 1 month
  • Last seen this week
  • United States
19 votes
Accepted

Integer polynomials mapping the unit disk into itself

14 votes

What is the probability that two numbers are relatively prime?

13 votes

Is the series $\sum_n|\sin n|^n/n$ convergent?

12 votes

$\prod_{n=1}^{\infty} n^{\mu(n)}=\frac{1}{4 \pi ^2}$

10 votes
Accepted

A technical question related to Zhang's result of bounded prime gaps

10 votes
Accepted

Estimation of $\sum_{n \leq x} \frac{k(n)}{n}$ , with $k(n)$ the squarefree kernel

9 votes
Accepted

Any closed form for series like $F(x)=\sum\limits_{p=2}^{\infty}x^p,$ where $p$ is prime?

8 votes

How does Yitang Zhang use Cauchy's inequality and Theorem 2 to obtain the error term coming from the $S_2$ sum

8 votes
Accepted

sum of $1/ \phi(n)^2$

7 votes

Counterexamples in algebra?

7 votes

Number of distinct factors

7 votes

Is ${\rm lcm}\{{\rm ord}_p(q)\colon q\mid p-1,\ q>2\}>\sqrt p\ \,$?

7 votes

Distribution of the Error term in GH Hardy's "curious result" $\sum_{\nu \leq n } \{ \nu \theta \}^2 = \tfrac{1}{12} n + O(1)$

7 votes

On an example of an eventually oscillating function

6 votes
Accepted

Arithmetic progressions in inverse image of totient function

6 votes

Correlations of $\phi(n)/n$

6 votes
Accepted

Smith normal form of a Matrix with -1 outside the diagonal

5 votes

Riemann zeta at even integers

5 votes

Can we estimate the error $\left| \frac{1}{N^2} \sum f ( \{ \sqrt{2} m + \sqrt{3} n \} ) - \int_0^1 f(x) \, dx \right|$?

5 votes
Accepted

Upper bounds on the irrationality measure of the arctan of an algebraic number

5 votes
Accepted

Reference for inequality for $\sum\limits_{d \mid n}\frac{\log d}{d}.$

5 votes
Accepted

Perfectly balanced sets of complex numbers

4 votes
Accepted

Divisor Function of Highly Composite Numbers

4 votes

Is there a row vector $x$ with integer entries such that no entry of $xM$ is $0 \text{ (mod }p\text{)}$?

4 votes

Sums of inverse determinants over matrices

4 votes

Extension of pointwise convergence of a sequence of uniformly continuous functions that converges on a dense set

3 votes
Accepted

Find generating function

3 votes
Accepted

Generalized multinomial coefficient

3 votes

Trig functions based on convex curves

3 votes

Distribution of $n$-th roots modulo a smooth number