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Related papers: Short proofs of some extremal results II

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We generalize several classical theorems in extremal combinatorics by replacing a global constraint with an inequality which holds for all objects in a given class. In particular we obtain generalizations of Tur\'an's theorem, the…

Combinatorics · Mathematics 2022-05-30 David Malec , Casey Tompkins

We prove that certain classes of metrically homogeneous graphs omitting triangles of odd short perimeter as well as triangles of long perimeter have the extension property for partial automorphisms and we describe their Ramsey expansions.

According to Paul Erd\H{o}s [Some notes on Tur\'an's mathematical work, J. Approx. Theory 29 (1980), page 4] it was Paul Tur\'an who "created the area of extremal problems in graph theory". However, without a doubt, Paul Erd\H{o}s…

Combinatorics · Mathematics 2016-02-22 Vojtěch Rödl , Mathias Schacht

We consider linear partial differential equations on resistance spaces that are uniformly elliptic and parabolic in the sense of quadratic forms and involve abstract gradient and divergence terms. Our main interest is to provide graph and…

Functional Analysis · Mathematics 2020-09-15 Michael Hinz , Melissa Meinert

This paper proves several weak limit theorems for the joint version of extreme order statistics and partial sums of independently and identically distributed random variables. The results are also extended to almost sure limit version.

Probability · Mathematics 2023-12-18 Gaoyu Li , Zhongquan Tan

Recently, Ali et al. posed several open problems concerning extremal graphs with respect to the ABS index. These problems involve characterizing graphs that attain the maximum ABS index within specific graph classes, including: connected…

Combinatorics · Mathematics 2025-12-30 Swathi Shetty , B. R. Rakshith , Sayinath Udupa N.

We give an abstract approach to finite Ramsey theory and prove a general Ramsey-type theorem. We deduce from it a self-dual Ramsey theorem, which is a new result naturally generalizing both the classical Ramsey theorem and the dual Ramsey…

Combinatorics · Mathematics 2013-09-12 Slawomir Solecki

We solve two continuous extremal problems on the classes of monotone functions: in the first problem we find extremal values for a line integral of a coordinate-wise monotone function of two variables from a rearrange\-ment-invariant class…

Functional Analysis · Mathematics 2026-03-03 Oleg Kovalenko

We introduce the concept of geometric extremal graphical models, which are defined through the gauge function of the limit set obtained from suitably scaled random vectors in light-tailed margins. For block graphs, we prove results relating…

Statistics Theory · Mathematics 2026-01-05 Ioannis Papastathopoulos , Jennifer Wadsworth

The extremal characteristics of random structures, including trees, graphs, and networks, are discussed. A statistical physics approach is employed in which extremal properties are obtained through suitably defined rate equations. A variety…

Statistical Mechanics · Physics 2007-05-23 E. Ben-Naim , P. L. Krapivsky , S. Redner

We give an elementary, self-contained, and purely combinatorial proof of the Rayleigh monotonicity property of graphs.

Combinatorics · Mathematics 2017-07-31 J. Cibulka , J. Hladky , M. A. LaCroix , D. G. Wagner

An infinite graph is highly connected if the complement of any subgraph of smaller size is connected. We consider weaker versions of Ramsey's Theorem asserting that in any coloring of the edges of a complete graph there exist large highly…

Logic · Mathematics 2018-12-18 Jeffrey Bergfalk , Michael Hrušák , Saharon Shelah

This paper falls within the general program of investigating the proof theoretic strength (in terms of reverse mathematics) of combinatorial principals which follow from versions of Ramsey's theorem. We examine two statements in graph…

Logic · Mathematics 2011-01-04 Peter Cholak , David Galvin , Reed Solomon

A connected graph, on four or more vertices, is matching covered (aka 1-extendable) if every edge is present in some perfect matching. An ear decomposition theorem exists for bipartite matching covered graphs due to Hetyei. From the results…

Combinatorics · Mathematics 2026-05-21 Amit Kumar Mallik , Ajit A. Diwan , Nishad Kothari

Recent advances in our understanding of higher derived limits carry multiple implications in the fields of condensed and pyknotic mathematics, as well as for the study of strong homology. These implications are thematically diverse,…

Algebraic Topology · Mathematics 2025-08-12 Jeffrey Bergfalk , Chris Lambie-Hanson

Generalized Tur\'an problems have been a central topic of study in extremal combinatorics throughout the last few decades. One such problem is maximizing the number of cliques of size $t$ in a graph of a fixed order that does not contain…

Combinatorics · Mathematics 2024-03-01 Debsoumya Chakraborti , Da Qi Chen

We enumerate the connected graphs that contain a linear number of edges with respect to the number of vertices. So far, only the first term of the asymptotics was known. Using analytic combinatorics, i.e. generating function manipulations,…

Combinatorics · Mathematics 2016-04-26 Elie de Panafieu

We identify computability-theoretic properties enabling us to separate various statements about partial orders in reverse mathematics. We obtain simpler proofs of existing separations, and deduce new compound ones. This work is part of a…

Logic · Mathematics 2016-12-14 Ludovic Patey

We enumerate the connected graphs that contain a number of edges growing linearly with respect to the number of vertices. So far, only the first term of the asymptotics and a bound on the error were known. Using analytic combinatorics, ie…

Combinatorics · Mathematics 2018-10-12 Elie de Panafieu

We prove some results on the border of Ramsey theory (finite partition calculus) and model theory. Also a beginning of classification theory of finite models in undertaken.

Logic · Mathematics 2016-09-06 Doug Ensley , Rami Grossberg