so-called friend Don's user avatar
so-called friend Don's user avatar
so-called friend Don's user avatar
so-called friend Don
  • Member for 12 years, 8 months
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11 votes

Sum of the reciprocals of radicals

9 votes
Accepted

Factorizations of cyclotomic polynomials valuated at primes

6 votes
Accepted

Additive basis of a set union the square of the set

3 votes

Lower bound for Euler's totient for almost all integers

7 votes

Squares of the form $2^j\cdot 3^k+1$

7 votes

Numbers that don't start with (p-1) in base p for any p

4 votes

Is $\limsup_{x\to\infty}\big(\sum\limits_{d|3^x-1}{1/d}\big)/\big(\sum\limits_{p<x}1/p\big)<\infty$?

15 votes
Accepted

A naive question about the prime number theorem

4 votes
Accepted

A very slowly diverging series

7 votes
Accepted

Lower bound on Carmichael Function

8 votes
Accepted

1/2 Wilson's theorem

5 votes

A simultaneous generalization of the Grunwald-Wang and Dirichlet Theorems on primes

11 votes
Accepted

Existence of relative Dirichlet density of primes starting with 1

8 votes

Perfect powers in the solutions of a certain Pell equation

7 votes

Average class number formula for imaginary quadratic fields with prime discriminant

8 votes

Is it possible to show that :for $n \geq 1:\sigma(n!-1) $ never be prime and why $\sigma(n!-1)\bmod 10 $ at most is $0$?

2 votes
Accepted

Dense subset in a product of $p$-adic groups?

21 votes
Accepted

Does the least prime factor have a mean of some sort?

8 votes

Results on the largest prime factor of $2^n+1$

8 votes
Accepted

If the natural density (relative to the primes) exists, then the Dirichlet density also exists, and the two are equal

8 votes

Asymptotics of product of Euler's totient function (A001088)?

23 votes
Accepted

Does the sum $\sum_{n=1}^{\infty}\frac{1}{p_n(p_{n+1}-p_n)}$ converge?

7 votes
Accepted

If $N = {q^k}{n^2}$ is an odd perfect number given in Eulerian form, is $n$ squarefree?

10 votes
Accepted

Are there other integer solutions to the equation $9x^3 -1 = y^3$ besides $(x,y) =(1,2)$ and $(0, -1)$?

8 votes
Accepted

What is known about the largest prime divisor of the product of $k$ consecutive integers?

6 votes
Accepted

multiplicative functions of powers

9 votes
Accepted

How often is $2^n-1$ a number with few divisors?

6 votes
Accepted

Did Erdős prove there are two primes $4a+1, 4b+3$ between between $n$ and $2n$?

2 votes

Prime divisors of values of a polynomial on an infinite set

7 votes

Lower bounding the probability that $\gcd(t,N)≤B$, for a random $t$ and fixed (large) $N$