Results 1 to 10 of about 31,249 (173)
On a Sum Involving the Sum-of-Divisors Function [PDF]
Let σn be the sum of all divisors of n and let t be the integral part of t. In this paper, we shall prove that ∑n≤xσx/n=π2/6x log x+Oxlog x2/3log2 x4/3 for x⟶∞, and that the error term of this asymptotic formula is Ωx.
Feng Zhao, Jie Wu
doaj +3 more sources
Iterating the Sum-of-Divisors Function [PDF]
Let $\sigma^0(n) = n$ and $\sigma^m(n) = \sigma(\sigma^{m-1}(n))$, where $m\ge1$ and $\sigma$ is the sum-of-divisors function. We say that $n$ is $(m,k)$-perfect if $\sigma^m(n) = kn$. We have tabulated all $(2,k)$-perfect numbers up to $10^9$ and all $(3,k)$- and $(4,k)$-perfect numbers up to $2\cdot10^8$.
Cohen, Graeme L., te Riele, Herman J. J.
openaire +4 more sources
MacMahon's sum-of-divisors functions, Chebyshev polynomials, and Quasi-modular forms [PDF]
We investigate a relationship between MacMahon's generalized sum-of-divisors functions and Chebyshev polynomials of the first kind. This determines a recurrence relation to compute these functions, as well as proving a conjecture of MacMahon about their ...
Andrews, George E., Rose, Simon CF
core +3 more sources
On a modification of Set(n) [PDF]
A modification of the set Set(n) for a fixed natural number n is introduced in the form: Set(n, f), where f is an arithmetic function. The sets Set(n,φ), Set(n,ψ), Set(n,σ) are discussed, where φ, ψ and σ are Euler's function, Dedekind's function and the
Krassimir T. Atanassov, József Sándor
doaj +1 more source
The Dirichlet divisor problem over square-free integers and unitary convolutions [PDF]
We obtain an asymptotic formula for the sum ~D₂ of the divisors of all square-free integers less than or equal to x, with error term O(x^{1/2 + ε}). This improves the error term O(x^{3/4 + ε}) presented in [7] obtained via analytical methods.
André Pierro de Camargo
doaj +1 more source
We show that the recurrence relation deduced by Robbins and Osler et al for the sum of divisors function can be solved in terms of the complete Bell polynomials. Besides, the connection between and the number of representations of n as the sum of four triangular numbers allows obtain arecurrence relation where only participate the values of with m
R. Sivaraman +2 more
openaire +1 more source
Density bounds for the sum of divisors function [PDF]
Upper and lower bounds are presented for the density of the integers n n for which σ ( n ) / n ≧ x \sigma (n)/n \geqq x , where σ ( n ) \sigma (n) is the sum of divisors of n n , and
Wall, Charles R. +2 more
openaire +3 more sources
ON A SUM INVOLVING CERTAIN ARITHMETIC FUNCTIONS ON PIATETSKI–SHAPIRO AND BEATTY SEQUENCES
Let 𝑐, 𝛼, 𝛽 ∈ R be such that ...
T. Srichan
doaj +1 more source
Inequalities between some arithmetic functions, II [PDF]
As a continuation of Part I (see [1]), we offer new inequalities for classical arithmetic functions such as the Euler's totient function, the Dedekind's psi function, the sum of the positive divisors function, the number of divisors function, extended ...
Krassimir Atanassov +2 more
doaj +1 more source
Certain combinatoric Bernoulli polynomials and convolution sums of divisor functions [PDF]
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Kim, Daeyeoul +1 more
openaire +4 more sources

