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5 votes
0 answers
300 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
0 votes
0 answers
87 views

I am trying to find the maximum gap between any prime and the nearest prime (whether smaller or bigger)?

I am trying to find the maximum gap between any prime and the nearest prime number (whether smaller or bigger)? Here is what I have: Assuming: I don’t know whether any of the multiples that are ...
Isaac Brenig's user avatar
  • 1,415
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
0 votes
1 answer
98 views

Show No. of trailing zeros in base $p$ representation = power of prime $p$. .

Let $N$ be an integer $> 1$, and $p$ a prime, then need show: No. of trailing zeros in base $p$ representation = power of prime $p$ in prime factorization. Say, $N= 31500 = 2002000_5$, and $31500= ...
jiten's user avatar
  • 4,534
1 vote
1 answer
25 views

Can you just assume without proof for coprime bases?

Let $x,y ∈ \mathbb{Z}$ and $a,b ∈ \mathbb{Z+}$, where $a\ne b$ and a,b are coprime Let $a^x=b^y$ The only solution is when $x = 0$ and $y = 0$, but is it necessary to prove it? I've got as far as ...
Oliver's user avatar
  • 113
1 vote
0 answers
142 views

How many divisors does an integer with prime factorization have

Let $n$ be an integer with prime factorization $n = p_1^{n_1} p_2^{n_2} ... p_k^{n_k}$ , where the $p_i$ are distinct primes. How many positive divisors does the integer $n$ have? Here is what I have: ...
mathstudent288's user avatar
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
1 vote
0 answers
63 views

Prove or disprove that $\frac{(x+n)!}{x!}$ is not divisible by $n$ distinct primes where each prime is greater than $\frac{(x+n)e}{n}$

Is it true that for integers $n > e, x \ge n$, it is impossible for $\dfrac{(x+n)!}{x!}$ to be divisible by $n$ distinct primes where each prime is greater than $\dfrac{(x+n)e}{n}$? Example: $x=n=...
Larry Freeman's user avatar
1 vote
1 answer
135 views

Prove that, for every natural number, their factorization as primes is unique

I need some feedback on this proof I wrote that: $$\forall n\in\mathbb{N} \text{ assumed the existence of a factorization of } n \text{ as } n = p_1p_2\cdots p_k, \text{ where } p_i, (1 \leq i \leq k)...
Samuele B.'s user avatar
1 vote
0 answers
31 views

Does it follow that there are at most $n+\pi(n-1)$ distinct primes that divide $\dfrac{(x+n)!}{x!}$

I've been thinking about the total number of distinct primes and it occurred to me that for any integers $x > 0, n > 0$, there are at most $n+\pi(n-1)$ distinct primes that divide $\dfrac{(x+n)!}...
Larry Freeman's user avatar
1 vote
0 answers
50 views

Finding the number of divisors that satisfy some condition - What am I doing wrong?

Let $N$ = $2^1$$^5%$$3^1$$^6$. How many divisors of $N^2$ less than $N$ are there which don't divide $N$ MY ATTEMPT: We have: $N^2$ = $2^3$$^0%$$3^3$$^2$. The number of divisors of $N^2$ which do ...
MNIShaurya's user avatar
2 votes
1 answer
639 views

Prime elements in the subring $R = \mathbb Z + x \mathbb Q[x]$ of $ \mathbb Q[x]$

Two questions I was given and want to make sure my reasoning is correct. (1) Show that if $p$ is prime in $Z$, then $p$ is prime in $R = \mathbb Z + x \mathbb Q[x]$ (the subring of polynomials ...
jmac's user avatar
  • 151
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
1 vote
1 answer
169 views

Degree $3$ polynomial with constant coefficient $2010$

$\mathbf{Statement}$: Let $P$ be a degree $3$ polynomial with complex coefficients such that the constant term is $2010$. Then $P$ has a root $\alpha$ with $|\alpha|>10$. (TRUE OR FALSE?). ...
Subhasis Biswas's user avatar
2 votes
2 answers
150 views

A proof of the existence of prime numbers right after 'booting-up' the counting numbers?

Not sure if the following argument is circular in nature or breaks down in some other way. We've defined the counting numbers $n \ge 1$ with the two familiar binary operations of addition and ...
CopyPasteIt's user avatar
  • 11.5k

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