Results 61 to 70 of about 63,567 (182)

The k-Zero-Divisor Hypergraph of a Commutative Ring

International Journal of Mathematics and Mathematical Sciences, 2007
The concept of the zero-divisor graph of a commutative ring has been studied by many authors, and the k-zero-divisor hypergraph of a commutative ring is a nice abstraction of this concept.
Ch. Eslahchi, A. M. Rahimi
doaj   +1 more source

Exponential and infinitary divisors [PDF]

, 2014
Our paper is devoted to several problems from the field of modified divisors: namely exponential and infinitary divisors. We study the behaviour of modified divisors, sum-of-divisors and totient functions.
Lelechenko, Andrew V.
core  

Panel Sequential Group Estimation of Interactive Effects Models

Oxford Bulletin of Economics and Statistics, EarlyView.
ABSTRACT This paper proposes a novel procedure to identify latent groups in the slopes of panel data models with interactive effects. The method is straightforward to apply and relies only on closed‐form estimators when evaluating the objective function.
Ignace De Vos, Joakim Westerlund
wiley   +1 more source

New Proof That the Sum of the Reciprocals of Primes Diverges

Mathematics, 2020
In this paper, we give a new proof of the divergence of the sum of the reciprocals of primes using the number of distinct prime divisors of positive integer n, and the placement of lattice points on a hyperbola given by n=pr with prime number p.
Vicente Jara-Vera, Carmen Sánchez-Ávila   +1 more
doaj   +1 more source

The Mathematical History Behind the Granger–Johansen Representation Theorem

Oxford Bulletin of Economics and Statistics, EarlyView.
ABSTRACT When can a vector time series that is integrated once (i.e., becomes stationary after taking first differences) be described in error correction form? The answer to this is provided by the Granger–Johansen representation theorem. From a mathematical point of view, the theorem can be viewed as essentially a statement concerning the geometry of ...
Johannes M. Schumacher
wiley   +1 more source

On unitary Zumkeller numbers [PDF]

Notes on Number Theory and Discrete Mathematics
It is well known that if n is a Zumkeller number, then the positive divisors of n can be partitioned into two disjoint subsets of equal sum. Similarly for unitary Zumkeller number n, the unitary divisors of n can be partitioned into two disjoint subsets ...
Bhabesh Das
doaj   +1 more source

The 3‐sparsity of Xn−1$X^n-1$ over finite fields of characteristic 2

Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract Let q$q$ be a prime power and Fq$\mathbb {F}_q$ the finite field with q$q$ elements. For a positive integer n$n$, the polynomial Xn−1∈Fq[X]$X^n - 1 \in \mathbb {F}_q[X]$ is termed 3‐sparse over Fq$\mathbb {F}_q$ if all its irreducible factors in Fq[X]$\mathbb {F}_q[X]$ are either binomials or trinomials.
Kaimin Cheng
wiley   +1 more source

Rational points on even‐dimensional Fermat cubics

Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract We show that even‐dimensional Fermat cubic hypersurfaces are rational over any field of characteristic not equal to three, by constructing explicit rational parameterizations with polynomials of low degree. As a byproduct of our rationality constructions, we obtain estimates for the number of their rational points over a number field and ...
Alex Massarenti
wiley   +1 more source

Arithmetic functions associated with infinitary divisors of an integer

International Journal of Mathematics and Mathematical Sciences, 1993
The infinitary divisors of a natural number n are the products of its divisors of the form pyα2α, where py is a prime-power component of n and ∑αyα2α (where yα=0 or 1) is the binary representation of y.
Graeme L. Cohen, Peter Hagis
doaj   +1 more source

Degree theory for 4‐dimensional asymptotically conical gradient expanding solitons

Communications on Pure and Applied Mathematics, Volume 79, Issue 5, Page 1151-1298, May 2026.
Abstract We develop a new degree theory for 4‐dimensional, asymptotically conical gradient expanding solitons. Our theory implies the existence of gradient expanding solitons that are asymptotic to any given cone over S3$S^3$ with non‐negative scalar curvature. We also obtain a similar existence result for cones whose link is diffeomorphic to S3/Γ$S^3/\
Richard H. Bamler, Eric Chen
wiley   +1 more source