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Comment by Command Master on for which $A\subset \mathbb{N}$ does there exist...

Intuitively it seems to me that almost all sequences should work for all numbers, even if you make them grow exponentially

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Comment by Command Master on Maximizing a sum minus its maximal summand

You might want to fix (an upper bound to) $\max i\pi_i$ and then maximize $\sum i\pi_i$ as a function of that, and then maximize that.

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Comment by Command Master on Is Reciprocal Fibonacci constant irrational?

The reciprocal prime Fibonacci constant being irrational implies there are infinitely many Fibonacci primes, which is an open problem.

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Comment by Command Master on A question about the prime counting function

Is there a reason this question is framed in terms of $n+1$ and not $n$ ($\pi(n^2) < \frac{(n+1)^2}{\ln((n+1)^2)}$)?

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Comment by Command Master on Approximating a fraction with a given denominator

@mtheorylord There are many algorithms for this — just search "two variable jnteger programming"

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Comment by Command Master on Does every real number $r\in [0,1]$ have a...

@JoachimKönig Thanks, I was wondering if that's the case

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Comment by Command Master on How to define a fractal from the lexicographic...

How is the factorization ordered? Are the primes in increasing order? The prime powers? Something else?

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Comment by Command Master on In what sense does the sentence...

The notion of omega-consistency might be relevant here - while there are (consistent) models of PA where $\neg \mathsf{con}(\mathsf{PA})$ holds, they aren't $\omega$-consistent.

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Comment by Command Master on Linear equation among divisors of a positive...

Intuitively this feels too restricted, perhaps the abc or n conjecture can show something

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Comment by Command Master on Why should we expect this odd behavior of...

It might be due to the fact that it only takes integers — can you try to graph the fractional part of $nq/p +2\sqrt{nq}/p$?

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Comment by Command Master on Repeated values of a monomial

Given two solutions $(h_1, m_1), (h_2, m_2)$, you have $\log(\frac{m_1}{m_0}) \log(\frac{h_2}{h_0}) = \log(\frac{m_2}{m_0})\log(\frac{h_1}{h_0})$. There might be something simple this implies which I'm...

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Comment by Command Master on Factorization trees and (continued) fractions?

@mathoverflowUser Each non-leaf node must have a leaf as a child, and that leaf has a value of $1$, so in $p(T_{n,m}, 1)$ the numerator is $1$ and the denominator is at least $1$, so $p(T_{n,m}, 1)...

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Comment by Command Master on Is it possible to write any Dirichlet series as...

Are you talking about Dirichlet series in general, or those of Dirichlet characters?

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Comment by Command Master on Is there a "halting machine" which halts on itself?

@EmilJeřábek thanks, I updated it. A quine is a program which outputs itself, so that's how I remembered it

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Answer by Command Master for Expected sorting time of random permutation...

Here's a proof that $\mathbf{E}[X] = O(n^2 \log^2(n))$. Let's assume WLOG $n$ is a power of 2. Let's calculated the expected time until all values bigger than $\frac{n}2$ are in the second half (and...

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Expected sorting time of random permutation using random comparators

In sorting networks, a comparator of positions $i < j$ is an operator which takes a permutation, checks if $p_i > p_j$, and if it is the case, swaps $p_i$ and $p_j$.Using this, we can define the...

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Asymptotic number of "modular primes"

We can say that a number $p$ is prime modulo $N$ if for any two numbers $1<a,b<p$, $ab \not\equiv p \pmod N$. We will define $p(n)$ to be the number of primes mod $n$. I'm wondering about the...

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Answer by Command Master for Residues distribution modulo an interval

Note that $n \equiv b-1 \pmod b$ implies $b | n+1$, $n \equiv b-2 \pmod b$ implies $b | n+2$, and so on. Therefore you can factor $n+1$, $n+2$, and so on, until one of them has a factor in $I$. You can...

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Efficiently count the number of primitive roots in all moduli up to $n$

Let's define $f(n)$ as the number of primitive roots modulo $n$. That is, $f(n) = \begin{cases}\varphi(\varphi(n))&n=1,2,4,p^k,2p^k\\0&\text{otherwise}\end{cases}$. We want to efficiently...

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Answer by Command Master for Illumination from visible lattice points with...

Let's look at the number of the representations of $n$ as $a^2 + b^2$ with coprime $a, b$, and denote it $v(n)$. Our sum is then $\sum_{n \leq r^2} {\frac{v(n)}{n}}$.We can see that $\sum_{d^2 | n}...

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