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5 votes
0 answers
305 views

Valid Elementary Proof of the Bertrand-Chebyshev Theorem/Bertrand's Postulate? [closed]

$\textbf{Theorem}$ (Bertrand-Chebyshev theorem/Bertrand's postulate): For all integers $n\geq 2$, there exists an odd prime number $p\geq 3$ satisfying $n<p<2n$. $\textit{Proof }$: For $n=2$, we ...
SurfaceIntegral's user avatar
1 vote
1 answer
113 views

Elements of the sequence have a prime factors an element of the sequence

I am reading the following problem: For the sequence $T=3, 7, 11, 15, 19, 23, 27 ...$ prove that every number in $T$ has a prime factor that is also in $T$ My approach: The sequence is of the form $...
Jim's user avatar
  • 1,609
2 votes
0 answers
37 views

Prime inert in each subfields never occurs

Suppose you are working with $K=\mathbb{Q}[\sqrt{m},\sqrt{n}]$ and $K_1=\mathbb{Q}[\sqrt{m}],K_2=\mathbb{Q}[\sqrt{n}], K_3=\mathbb{Q}[\sqrt{k}]$ where $m,n$ are squarefree integers and $k = mn/gcd(m,n)...
Davide Motta's user avatar
  • 1,078
0 votes
0 answers
214 views

Need help interpreting this formula for the number of Goldbach partitions

1: Formula for the number of Goldbach partitions. Let $g\left(n\right)$ denote the number of Goldbach partitions of even integer $2n$: $$g_{\left(n\right)}=\sum_{3\leq p\leq2n-3}\left[\pi\left(2n-p\...
François Huppé's user avatar
0 votes
1 answer
1k views

Prime Factorization of $m^2$

If $m$ is a positive integer, explain why each prime in the prime factorization of $m^2$ must occur an even number of times. I did a small proof, I was wondering what's a nice way to explain it aside ...
OLE's user avatar
  • 602
0 votes
0 answers
301 views

Proof that for a given prime $a$, there are only finite many carmichael-numbers $N=abc$ with $b,c$ prime

Please check if the following proof that for every prime $a$, the number of carmichael numbers $N=abc$ , where $b$ and $c$ are also prime, is finite, is correct! First of all, we have $$a-1|abc-1$$ $$...
Peter's user avatar
  • 85.1k
4 votes
2 answers
227 views

The Conjecture That There Is Always a Prime Between $n$ and $n+C\log^2n$

Let $n$ be 113. Use $n+C\log^2n$ to find the next consecutive prime or at least approximately how far away it is. Will you show me how to work this out step by step to show me how to use this formula? ...
Jeffrey Young's user avatar