The contractibility number (also known as the Hadwiger number) of a connected graph G, Z(G), is defined as the maximum order of a connected graph onto which G is contractible. An elementary proof is given of a theorem of Ore about this invariant. Also, the extremal problem of finding the maximum Z(G) over all graphs G of a given order and regularity degree is solved.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22731/1/0000286.pd
The aim of this note is to give an account of some recent results and state a number of conjectures ...
AbstractLet k be a positive integer and let G be a k-connected graph. An edge of G is called k-contr...
The Hadwiger number h(G) of a graph G is the maximum size of a complete minor of G. Hadwiger's Conje...
The contraction clique number ccl(G) of a graph G is the maximal r for which G has a subcontraction ...
AbstractThe Hadwiger number of a graph G = (V, E), denoted by η(G), is the maximum size of a complet...
AbstractConsider the following relaxation of the Hadwiger Conjecture: For each t there exists Nt suc...
The Degree Contractibility problem is to test whether a given graph G can be modified to a graph of ...
AbstractModifying a given graph to obtain another graph is a well-studied problem with applications ...
For a fixed graph H, the H-Contractibility problem asks if a graph is H-contractible, i.e., can be t...
For a fixed graph H, the H-Contractibility problem asks if a graph is H-contractible, i.e., can be t...
A graph $G$ is contractible to a graph $H$ if there is a set $X \subseteq E(G)$, such that $G/X$ is ...
A graph G is contractible to a graph H if there is a set X subseteq E(G), such that G/X is isomorphi...
In this paper we consider the effect of edge contraction on the domination number and total dominati...
For a graph parameter π, the Contraction(π) problem consists in, given a graph G and two positive in...
AbstractAn edge of a k-connected graph is said to be k-contractible if its contraction results in a ...
The aim of this note is to give an account of some recent results and state a number of conjectures ...
AbstractLet k be a positive integer and let G be a k-connected graph. An edge of G is called k-contr...
The Hadwiger number h(G) of a graph G is the maximum size of a complete minor of G. Hadwiger's Conje...
The contraction clique number ccl(G) of a graph G is the maximal r for which G has a subcontraction ...
AbstractThe Hadwiger number of a graph G = (V, E), denoted by η(G), is the maximum size of a complet...
AbstractConsider the following relaxation of the Hadwiger Conjecture: For each t there exists Nt suc...
The Degree Contractibility problem is to test whether a given graph G can be modified to a graph of ...
AbstractModifying a given graph to obtain another graph is a well-studied problem with applications ...
For a fixed graph H, the H-Contractibility problem asks if a graph is H-contractible, i.e., can be t...
For a fixed graph H, the H-Contractibility problem asks if a graph is H-contractible, i.e., can be t...
A graph $G$ is contractible to a graph $H$ if there is a set $X \subseteq E(G)$, such that $G/X$ is ...
A graph G is contractible to a graph H if there is a set X subseteq E(G), such that G/X is isomorphi...
In this paper we consider the effect of edge contraction on the domination number and total dominati...
For a graph parameter π, the Contraction(π) problem consists in, given a graph G and two positive in...
AbstractAn edge of a k-connected graph is said to be k-contractible if its contraction results in a ...
The aim of this note is to give an account of some recent results and state a number of conjectures ...
AbstractLet k be a positive integer and let G be a k-connected graph. An edge of G is called k-contr...
The Hadwiger number h(G) of a graph G is the maximum size of a complete minor of G. Hadwiger's Conje...
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