Results 61 to 70 of about 31,208 (175)
Noûs, EarlyView.ABSTRACT It is a truism of mathematics that differences between isomorphic number systems are irrelevant to arithmetic. This truism is deeply rooted in the modern axiomatic method and underlies most strands of arithmetical structuralism, the view that arithmetic is about some abstract number structure.
Balthasar Grabmayr
wiley +1 more source
Practical numbers and the distribution of divisors
, 2015 An integer $n$ is called practical if every $m\le n$ can be written as a sum of distinct divisors of $n$. We show that the number of practical numbers below $x$ is asymptotic to $c x/\log x$, as conjectured by Margenstern.
Weingartner, Andreas
core +1 more source
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
Anomaly Cancellation And Abelian Gauge Symmetries In F-theory
, 2012 We study 4D F-theory compactifications on singular Calabi-Yau fourfolds with fluxes. The resulting N=1 effective theories can admit non-Abelian and U(1) gauge groups as well as charged chiral matter.
Cvetič, Mirjam +2 more
core +1 more source
, 2017 The class of Lambert series generating functions (LGFs) denoted by $L_α(q)$ formally enumerate the generalized sum-of-divisors functions, $σ_α(n) = \sum_{d|n} d^α$, for all integers $n \geq 1$ and fixed real-valued parameters $α\geq 0$. We prove new formulas expanding the higher-order derivatives of these LGFs.
openaire +3 more sources
Quasi-modularity of generalized sum-of-divisors functions [PDF]
Research in Number Theory, 2015 11 ...
openaire +4 more sources
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
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
Extremal Problems for Subset Divisors [PDF]
, 2014 Let $A$ be a set of $n$ positive integers. We say that a subset $B$ of $A$ is a divisor of $A$, if the sum of the elements in $B$ divides the sum of the elements in $A$. We are interested in the following extremal problem.
Huynh, Tony
core
On the Foundational Arguments of Sufficient Dimension Reduction
WIREs Computational Statistics, Volume 18, Issue 2, June 2026.Contemporary Sufficient Dimension Reduction, a versatile method for extracting material information from data, can serve as a preprocessor for classical modeling and inference, or as a standalone theory that leads directly to statistical inference. ABSTRACT Sufficient dimension reduction (SDR) refers to supervised methods of dimension reduction that ...
R. Dennis Cook
wiley +1 more source