完全二部图的Gallai猜想

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  • 1. 安徽理工大学数学与大数据学院, 安徽淮南 232000
耿显亚, E-mail: gengxianya@sina.com

收稿日期: 2021-09-27

  网络出版日期: 2025-03-08

基金资助

国家自然科学基金(12171190);安徽省自然科学基金(2008085MA01)

版权

运筹学学报编辑部, 2025, 版权所有,未经授权,不得转载。

Gallai's conjecture for complete bipartite graphs

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  • 1. School of Mathematics and Big Data, Anhui University of Science & Technology, Huainan 232000, Anhui, China

Received date: 2021-09-27

  Online published: 2025-03-08

Copyright

, 2025, All rights reserved. Unauthorized reproduction is prohibited.

摘要

$G$是具有$n$个顶点的简单连通图。Gallai于1966年提出关于图的路分解猜想: 每个$n$阶简单连通图$G$都可以被分解为至多$\left\lceil\frac{n}{2}\right\rceil$条路。在本文中, 我们利用算法证明了Gallai猜想对于完全二部图$K_{n_1, n_2}$成立, 这里1≤n2 < n1n1是奇数。结合Constantinou和Ellinas (2018)的结果, 我们证明了对于任意的完全二部图, Gallai猜想成立。

本文引用格式

耿显亚, 柴惠 . 完全二部图的Gallai猜想[J]. 运筹学学报, 2025 , 29(1) : 232 -238 . DOI: 10.15960/j.cnki.issn.1007-6093.2025.01.020

Abstract

Let $G$ be a connected simple graph on $n$ vertices. The Gallai's conjecture (1966) asserts that every simple connected graph $G$ on $n$ vertices can be decomposed into at most $\left\lceil\frac{n}{2}\right\rceil$ paths. In this paper, we prove that Gallai's conjecture is true for each complete bipartite graph $K_{n_1, n_2}, $ where 1≤n2 < n1 and n1 is odd. Together with the conclusions of [1], we show that Gallai's conjecture holds for all complete bipartite graphs.

参考文献

1 Lovász L. On covering of graphs [M]//Erdos P, Katona G (eds). Theory of Graphs, New York: Academin Press, 1968: 231-236.
2 Fan G H . Path decompositions and Gallai's conjecture[J]. Journal of Combinatorial Theory, Series B, 2005, 93 (2): 117- 125.
3 Favaron O , Kouider M . Path partitions and cycle partitions of Eulerian graphs of maximum degree 4[J]. Studia Scientiarum Mathematicarum Hungarica, 1988, 1, 237- 244.
4 Geng X Y , Fang M L , Li D Q . Gallai's conjecture for outerplanar graphs[J]. Journal of Interdisciplinary Mathematics, 2015, 18 (5): 593- 598.
5 Alspach B . The wonderful Walecki construction[J]. Bulletin of the Institute of Combinatorics and Its Applications, 2008, 52, 7- 20.
6 Bryant D . Packing paths in complete graphs[J]. Journal of Combinatorial Theory, 2010, 100 (2): 206- 215.
7 Fu C M , Huang K C , Mishima M . Decomposition of complete bipartite graphs into cycles of distinct even lengths[J]. Graphs and Combinatorics, 2016, 32 (4): 1397- 1413.
8 Parker C. Complete bipartite graph path decompositions [D]. Alabama: Auburn University, 1998.
9 Zhai M Q , Lu C H . Path decomposition of graphs with given path length[J]. Acta Mathematicae Applicatae Sinica, 2006, 22 (4): 633- 638.
10 Haggkvist R , Johansson R . A note on edge-decompositions of planar graphs[J]. Discrete Mathematics, 2004, 283, 263- 266.
11 Thomassen C . Edge-decompositions of highly connected graphs into paths[J]. Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg, 2008, 78 (1): 17- 26.
12 Heinrich K . Path-decompositions[J]. Matematiche, 1992, 47 (2): 241- 258.
13 Tarsi M . Decomposition of a complete multigraph into simple paths: nonbalanced handcuffed designs[J]. Journal of Combinatorial Theory, Series A, 1983, 34 (1): 60- 70.
14 Pyber L . Covering the edges of a connected graph by paths[J]. Journal of Combinatorial Theory, Series B, 1996, 66 (1): 152- 159.
15 Donald A . An upper bound for the path number of a graph[J]. Journal of Graph Theory, 1980, 4 (2): 189- 201.
16 Constantinou C K , Ellinas G . Minimal path decomposition of complete bipartite graphs[J]. Journal of Combinatorial Optimization, 2018, 35, 684- 702.
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