English
Related papers

Related papers: About Very Perfect Numbers

200 papers

In this note, we show that if $N$ is an odd perfect number and $q^{\alpha}$ is some prime power exactly dividing it, then $\sigma(N/q^{\alpha})/q^{\alpha}>5$. In general, we also show that if $\sigma(N/q^{\alpha})/q^{\alpha}<K$, where $K$…

Number Theory · Mathematics 2016-12-08 Jose Arnaldo B. Dris , Florian Luca

We know that any prime number of form $4s+1$ can be written as a sum of two perfect square numbers. As a consequence of Goldbach's weak conjecture, any number great than $10$ can be represented as a sum of four primes. We are motivated to…

Number Theory · Mathematics 2017-05-24 Haifeng Xu

We prove that an odd number is an Euler pseudoprime for exactly one half of the admissible bases if and only if it is a special Carmichael number.

Number Theory · Mathematics 2011-09-19 Lorenzo Di Biagio

We will show the two following results: If there existe an odd perfect number $n$ of prime decomposition $n=p_1^{\alpha_1} \ldots p_k^{\alpha_k}q^\beta$, where the $\alpha_i$ are even, the $\beta$ are odd and $q \equiv 5 \mod 8$. Then there…

History and Overview · Mathematics 2016-10-04 Nancy Wallace

In this paper, it is proved that every sufficiently large even integer can be represented as the sum of two squares of primes, two cubes of primes, two biquadrates of primes and 16 powers of 2. Furthermore, there are at least 5.313% odd…

Number Theory · Mathematics 2024-01-04 Yuhui Liu

A well-known conjecture asserts that there are infinitely many primes $p$ for which $p - 1$ is a perfect square. We obtain upper and lower bounds of matching order on the number of pairs of distinct primes $p,q \le x$ for which $(p - 1)(q -…

Number Theory · Mathematics 2015-07-23 Tristan Freiberg , Carl Pomerance

We extend our previous work on odd spoof multiperfect numbers to the case where spoof factor multiplicities exceed $2$. This leads to the identification of $11$ new integers that would be odd multiperfect numbers if one of their prime…

Number Theory · Mathematics 2025-10-03 László Tóth

A natural number $n$ is called {\it multiperfect} or {\it$k$-perfect} for integer $k\ge2$ if $\sigma(n)=kn$, where $\sigma(n)$ is the sum of the positive divisors of $n$. In this paper, we establish the structure theorem of odd multiperfect…

Number Theory · Mathematics 2011-02-23 Shi-Chao Chen , Hao Luo

Here is a square problem: in a unit square, is there a point with four rational distances to the vertices? A probability argument suggests a negative answer. This paper proves several special cases of the square problem: if the point sits…

General Mathematics · Mathematics 2021-05-14 Yang Ji

This paper discusses prime numbers that are (resp. are not) congruent numbers. Particularly the only case not fully covered by earlier results, namely primes of the form $p=8k+1$, receives attention.

Number Theory · Mathematics 2021-05-05 Tim Evink , Jaap Top , Jakob Dirk Top

We shall prove that if $N=p^\alpha q_1^{2\beta_1} q_2^{2\beta_2} \cdots q_{r-1}^{2\beta_{r-1}}$ is an odd perfect number such that $p, q_1, \ldots, q_{r-1}$ are distinct primes, $p\equiv\alpha\equiv 1\mod{4}$ and $t$ divides $2\beta_i+1$…

Number Theory · Mathematics 2024-02-27 Tomohiro Yamada

We shall show that there is no odd perfect number of the form $2^n+1$ or $n^n+1$.

Number Theory · Mathematics 2020-10-20 Tomohiro Yamada

We study the problem of perfect tiling in the plane and exploring the possibility of tiling a rectangle using integral distinct squares. Assume a set of distinguishable squares (or equivalently a set of distinct natural numbers) is given,…

Computational Geometry · Computer Science 2025-03-14 Bahram Sadeghi Bigham , Mansoor Davoodi , Samaneh Mazaheri , Jalal Kheyrabadi

For a positive integer $n$, if $\sigma(n)$ denotes the sum of the positive divisors of $n$, then $n$ is called a deficient perfect number if $\sigma(n)=2n-d$ for some positive divisor $d$ of $n$. In this paper, we prove some results about…

Number Theory · Mathematics 2019-06-25 Parama Dutta , Manjil P. Saikia

If $N = {p^k}{m^2}$ is an odd perfect number with special prime factor $p$, then it is proved that ${p^k} < (2/3){m^2}$. Numerical results on the abundancy indices $\frac{\sigma(p^k)}{p^k}$ and $\frac{\sigma(m^2)}{m^2}$, and the ratios…

Number Theory · Mathematics 2012-06-18 Jose Arnaldo B. Dris

In a paper published by this author in www.academia.edu(see reference[3]), it was established that there exist no three positive integers which are consecutive terms of an arithmetic progression; and whose sum of squares is a perfect or…

General Mathematics · Mathematics 2013-11-27 Konstantine Zelator

The chronicle of prime numbers travel back thousands of years in human history. Not only the traits of prime numbers have surprised people, but also all those endeavors made for ages to find a pattern in the appearance of prime numbers has…

General Mathematics · Mathematics 2022-09-27 Tashreef Muhammad , G. M. Shahariar , Tahsin Aziz , Mohammad Shafiul Alam

Let $\mathbf H_2$ denote the set of even integers $n \not\equiv 1 \pmod 3$. We prove that when $H \ge X^{0.33}$, almost all integers $n \in \mathbf H_2$, $X < n \le X + H$ can be represented as the sum of a prime and the square of a prime.…

Number Theory · Mathematics 2010-08-23 A. V. Kumchev , J. Y. Liu

An odd prime $p$ is called irregular with respect to Euler polynomials if it divides the numerator of one of the numbers $$E_1(0),E_{3}(0),\ldots,E_{p-2}(0),$$ where $E_n(x)$ is the $n$-th Euler polynomial. As in the classical case, we link…

Number Theory · Mathematics 2018-09-26 Su Hu , Min-Soo Kim , Min Sha

We prove that every odd number $N$ greater than 1 can be expressed as the sum of at most five primes, improving the result of Ramar\'e that every even natural number can be expressed as the sum of at most six primes. We follow the circle…

Number Theory · Mathematics 2012-07-05 Terence Tao