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English version:
Journal of Applied and Industrial Mathematics, 2019, 13:1, 85-92

Volume 26, No 1, 2019, P. 74-88

UDC 519.174.3
D. S. Malyshev and D. B. Mokeev
König graphs with respect to the 4-path and its spanning supergraphs

Abstract:
We describe the class of graphs whose every subgraph has the next property: The maximal number of disjoint 4-paths is equal to the minimal cardinality of sets of vertices such that every 4-path in the subgraph contains at least one of these vertices. We completely describe the set of minimal forbidden subgraphs for this class. Moreover, we present an alternative description of the class based on the operations of edge subdivision applied to bipartite multigraphs and the addition of the so-called pendant subgraphs, isomorphic to triangles and stars.
Illustr. 1, bibliogr. 19.

Keywords: subgraph packing, vertex cover of a subgraph, 4-path, König graph.

DOI: 10.33048/daio.2019.26.606

Dmitry S. Malyshev 1,2
Dmitry B. Mokeev 1,2

1. National Research University “Higher School of Economics”,
25/12 Bolshaya Pechyorskaya Street, 603155 Nizhny Novgorod, Russia
2. Lobachevsky Nizhny Novgorod State University,
23 Gagarin Avenue, 603950 Nizhny Novgorod, Russia
e-mail: dsmalyshev@rambler.ru, MokeevDB@gmail.com

Received December 12, 2017
Revised October 30, 2018
Accepted November 28, 2018

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