Geodesic
Nonempty intersection of longest paths in a graph with a small matching number
Czechoslovak Mathematical Journal, Tome 65 (2015) no. 2, pp. 545-553 Cet article a éte moissonné depuis la source Czech Digital Mathematics Library

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A maximum matching of a graph $G$ is a matching of $G$ with the largest number of edges. The matching number of a graph $G$, denoted by $\alpha '(G)$, is the number of edges in a maximum matching of $G$. In 1966, Gallai conjectured that all the longest paths of a connected graph have a common vertex. Although this conjecture has been disproved, finding some nice classes of graphs that support this conjecture is still very meaningful and interesting. In this short note, we prove that Gallai's conjecture is true for every connected graph $G$ with $\alpha '(G)\leq 3$.
A maximum matching of a graph $G$ is a matching of $G$ with the largest number of edges. The matching number of a graph $G$, denoted by $\alpha '(G)$, is the number of edges in a maximum matching of $G$. In 1966, Gallai conjectured that all the longest paths of a connected graph have a common vertex. Although this conjecture has been disproved, finding some nice classes of graphs that support this conjecture is still very meaningful and interesting. In this short note, we prove that Gallai's conjecture is true for every connected graph $G$ with $\alpha '(G)\leq 3$.
DOI : 10.1007/s10587-015-0193-2
Classification : 05C38, 05C70, 05C75
Keywords: longest path; matching number 
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Chen, Fuyuan. Nonempty intersection of longest paths in a graph with a small matching number. Czechoslovak Mathematical Journal, Tome 65 (2015) no. 2, pp. 545-553. doi: 10.1007/s10587-015-0193-2

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