The present volume honouring Vera Sos and Andras Hajnal contains survey articles (with classical theorems and state-of-the-art results) and cutting edge expository research papers with new theorems and proofs in the area of the classical Hungarian subjects, like extremal combinatorics, colorings, combinatorial number theory, etc.

A Unifying Generalization of Sperner’s Theorem.- A Quick Proof of Sprindzhuk’s Decomposition Theorem.- Discrepancy in Graphs and Hypergraphs.- Biplanar Crossing Numbers I: A Survey of Results and Problems.- An Exercise on the Average Number of Real Zeros of Random Real Polynomials.- Edge-Connection of Graphs, Digraphs, and Hypergraphs.- Perfect Powers in Products with Consecutive Terms from Arithmetic Progressions.- The Topological Version of Fodor’s Theorem.- Color-Critical Graphs and Hypergraphs with Few Edges: A Survey.- Pseudo-random Graphs.- Bounds and Extrema for Classes of Graphs and Finite Structures.- Relaxing Planarity for Topological Graphs.- Notes on CNS Polynomials and Integral Interpolation.- The Evolution of an Idea — Gallai’s Algorithm.- On the Number of Additive Representations of Integers.- A Lifting Theorem on Forcing LCS Spaces.- Extremal Functions for Graph Minors.- Periodicity and Almost-Periodicity.

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