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Bound on the number of maximum matchings in a graph

It is known that the number of perfect matchings in a graph is bounded above by the integer part of the square root of the permanent of its adjacency matrix. But, suppose I take the square root of the ...
vidyarthi's user avatar
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0 votes
1 answer
150 views

Combining three matchings to form a maximal matching

Consider a regular tripartite graph $G$ with maximum degree $\Delta\ge3$ and parts $A,B,C$. Now, the induced subgraphs $A\cup B, B\cup C$ and $A\cup C$ are all bipartite. Now, is there a way to ...
vidyarthi's user avatar
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-1 votes
2 answers
306 views

Cardinality of a set of mutually disjoint perfect matchings of $K_\omega$

If $G=(V,E)$ is a simple, undirected graph, we say that $M\subseteq E$ is a perfect matching if the members of $M$ are pairwise disjoint and $\bigcup M = V$. Let $K_\omega$ be the complete graph on $\...
Dominic van der Zypen's user avatar
-2 votes
1 answer
362 views

Infinite graphs with large degree but no perfect matching [duplicate]

Is there an example of an infinite connected, simple, undirected graph $G = (V,E)$ such that every vertex has $|V|$ neighbors, but $G$ does not have a perfect matching (that is, a set $M\subseteq E$ ...
Dominic van der Zypen's user avatar
-2 votes
1 answer
74 views

Matching and minimal degree

Let $n\in\mathbb{N}$ be a positive integer and let $G =(V,E)$ be a connected simple undirected graph with $|V| = 2n$. Is it true that if for the minimal degree $\delta(G)$ we have $\delta(G) \geq n$, ...
Dominic van der Zypen's user avatar
-3 votes
1 answer
125 views

Does the Hadwiger-Nelson graph have a perfect matching?

The Hadwiger-Nelson graph on $\mathbb{R}^n$ is defined to be $(\mathbb{R}^n,E_n)$ where $$E_n = \big\{\{x,y\}: x,y\in \mathbb{R}^n \text{ and } |x-y|=1\big\},$$ where $|\cdot|$ denotes the Euclidean ...
Dominic van der Zypen's user avatar

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