Skip to main content

All Questions

Filter by
Sorted by
Tagged with
32 votes
3 answers
8k views

Ideas in the elementary proof of the prime number theorem (Selberg / Erdős)

I'm reading the elementary proof of prime number theorem (Selberg / Erdős, around 1949). One key step is to prove that, with $\vartheta(x) = \sum_{p\leq x} \log p$, $$(1) \qquad\qquad \vartheta(x) \...
Basj's user avatar
  • 587
13 votes
3 answers
1k views

At what point would an elementary generalization of Bertrand's Postulate be interesting?

I know that in 1952 Jitsuro Nagura was able to show that there is always a prime between $k$ and $\frac{6k}{5}$ for $k > 24$. At what point would an improvement on Nagura's result be interesting? ...
Larry Freeman's user avatar
7 votes
2 answers
636 views

How to use the Prime Number Theorem in order to prove Selberg's Formula?

I`m reading Melvin B. Nathanson's "Elementary Methods in Number Theory" and I can't think of a way of deducing Selberg's formula (9.3) from the prime number theorem. This is one of the tasks ...
Juu's user avatar
  • 129
6 votes
1 answer
826 views

Going beyond the Sylvester and Schur theorem with regard to $x,x+1,\dots,x+n-1$

I was recent reading through Paul Erdos's classic elementary proof of Sylvester-Schur. It occurred me that there is a simple argument that when $x$ is sufficiently large and if $p_i$ represents the $...
Larry Freeman's user avatar
6 votes
0 answers
381 views

A possible variant of Zagier's one-sentence proof for Fermat's sum of two squares theorem?

Is it possible to modify Zagier's one-sentence proof of Fermat's sum of two squares theorem (see here) to prove certain non-trivial cases of Jacobi's four-square theorem (see here)? Let $p$ be a prime ...
Mathew's user avatar
  • 81
3 votes
0 answers
1k views

Formula for $\pi$ involving exponents of Mersenne primes

Can someone provide a proof for the following claim? $$\pi=\dfrac{S_0S_2}{M_3M_5} \cdot\left(\displaystyle\prod_{p \equiv 1 \pmod{4} } \frac{p}{p-1}\right) \cdot \left(\displaystyle\prod_{p \equiv 3 \...
Pedja's user avatar
  • 2,661
1 vote
0 answers
127 views

Some property of the greatest prime factor

Let $n$ be a positive integer $\geq 2$ et denote by $ P^{+}(n)$ the greatest prime factor of $n$ my question is as follows: If $a$ and $b$ are two numbers, is there any method to express or to bound $...
Khadija Mbarki's user avatar