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Related papers: Nonexistence of Euler Boxes with Semiprime Sides

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The relevance of this paper lies in the fact that it resolves two previously unsolved open problems. In the first part of the paper, a new lemma is proved, from which it follows that if there exists a triangle with integer sides and…

Combinatorics · Mathematics 2026-03-24 Logman Shihaliev

In the present paper we prove Liouville-type theorems: non-existence theorems for some complete Riemannian almost product manifolds and special mappings of complete Riemannian manifolds which generalize similar results for compact…

Differential Geometry · Mathematics 2016-07-22 Stepanov Sergey

We study outer billiard systems around a class of circular sectors. For semi-discs, we prove the existence of elliptic islands occupying a positive proportion of the plane. Combined with known results, this shows the coexistence of…

Dynamical Systems · Mathematics 2025-06-24 Zaicun Li

Applying the method of moving planes in integral forms, we establish radial symmetry for positive solutions to a class of semilinear equations involving the fractional Laplacian in the unit ball and obtain Liouville type theorems concerning…

Analysis of PDEs · Mathematics 2013-10-01 Wenxiong Chen , Yanqin Fang , Ray Yang

In this short paper we prove that the square of an odd prime number cannot be a very perfect number.

General Mathematics · Mathematics 2008-12-04 Mihaly Bencze , Florin Popovici , Florentin Smarandache

We show that the number of partitions of n with alternating sum k such that the multiplicity of each part is bounded by 2m+1 equals the number of partitions of n with k odd parts such that the multiplicity of each even part is bounded by m.…

Combinatorics · Mathematics 2012-08-23 William Y. C. Chen , Ae Ja Yee , Albert J. W. Zhu

We study perfect codes in the sum-rank metric, a generalization of both the Hamming and rank metrics relevant in multishot network coding and space-time coding. A perfect code attains equality in the sphere-packing bound, corresponding to a…

Information Theory · Computer Science 2025-08-29 Giuseppe Del Prete , Antonio Roccolano , Ferdinando Zullo

In this paper, we recast a special case of Mahler'c conjecture by the maximum value of box splines. This is the case of polytopes with at most $2n+2$ facets. An asymptotic formula for univariate box splines is given. Based on the formula,…

Metric Geometry · Mathematics 2009-01-06 Zhiqiang Xu

The Umehara algebra is studied with motivation on the problem of the non-existence of common complex submanifolds. In this paper, we prove some new results in Umehara algebra and obtain some applications. In particular, if a complex…

Complex Variables · Mathematics 2022-11-03 Xu Zhang , Donghai Ji

We show that, for every set of $n$ points in the $d$-dimensional unit cube, there is an empty axis-parallel box of volume at least $\Omega(d/n)$ as $n\to\infty$ and $d$ is fixed. In the opposite direction, we give a construction without an…

Combinatorics · Mathematics 2021-02-26 Boris Bukh , Ting-Wei Chao

In this brief note, we give a simple information-theoretic proof that 2-state 3-symbol universal Turing machines cannot possibly exist, unless one loosens the definition of "universal".

Other Computer Science · Computer Science 2011-12-12 Craig Alan Feinstein

From the Levi's Theorem it is known that every finite dimensional Lie algebra over a field of characteristic zero is decomposed into semidirect sum of solvable radical and semisimple subalgebra. Moreover, semisimple part is the direct sum…

Rings and Algebras · Mathematics 2012-01-27 S. Gomez-Vidal , A. Kh. Khudoyberdiyev , B. A. Omirov

In this paper we analyze the existence of large positive radial solutions to some quasilinear elliptic systems. Also, a non-radially symmetric solution is obtained by using a lower and upper solution method. The equations are coupled by…

Classical Analysis and ODEs · Mathematics 2011-05-16 Dragos-Patru Covei

We examine the notion of strongly non-zero points and use it as a tool in the study of several types of elliptic pseudoprimes. Moreover, we give give some probabilistic results about the existence of strong elliptic pseudoprimes for a…

Number Theory · Mathematics 2021-03-10 L. Babinkostova , D. Fillmore , P. Lamkin , A. Lin , C. L. Yost-Wolff

It is proved that the derivation algebra of a centerless perfect Lie algebra of arbitrary dimension over any field of arbitrary characteristic is complete and that the holomorph of a centerless perfect Lie algebra is complete if and only if…

Quantum Algebra · Mathematics 2007-05-23 Yucai Su , Linsheng Zhu

We construct a weakly compact convex subset of $\ell^2$ with nonempty interior that has an isolated maximal element, with respect to the lattice order $\ell _+^2$. Moreover, the maximal point cannot be supported by any strictly positive…

Functional Analysis · Mathematics 2024-07-19 Aris Daniilidis , Carlo de Bernardi , Enrico Miglierina

We introduce the notion of c-nilpotent Schur Lie-multiplier of Leibniz algebras. We obtain exact sequences and formulas of the dimensions of the underlying vector spaces relating the c-nilpotent Schur Lie-multiplier of a Leibniz algebra Q…

Rings and Algebras · Mathematics 2017-10-30 G. R. Biyogmam , J. M. Casas

In this article we find the equivalent conditions to assure the existence and uniqueness of positive solutions to semilinear elliptic equations wih double power nonlinearities. As a bonus, we give a simpler proof of our former result that…

Analysis of PDEs · Mathematics 2008-11-07 Shinji Kawano

A rationality condition is derived for the existence of odd perfect numbers involving the square root of a product, which consists of a sequence of repunits, multiplied by twice the base of one of the repunits. This constraint also provides…

Number Theory · Mathematics 2007-05-23 Simon Davis

We prove the global existence of a helical weak solution of the 3D Euler equations, in full space, for an initial velocity with helical symmetry, without swirl and whose initial vorticity is compactly supported in the axial plane and…

Analysis of PDEs · Mathematics 2013-09-03 Anne C. Bronzi , Milton C. Lopes Filho , Helena J. Nussenzveig Lopes