Lower bound of the hadwiger number of graphs by their average degree
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چکیده
منابع مشابه
Lower bound of the Hadwiger number of graphs by their average degree
Let us recall the notion of the Hadwiger number. The following operations are called elementary contractions: substitution of two adjacent points vl and v~ for a new point vs connected to the points connected to v~ or v2; removal of an edge; removal of a point. The graph G is said to be contractable to the graph H if H can be obtained from G by means of a sequence of elementary contractions. Th...
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ژورنال
عنوان ژورنال: Combinatorica
سال: 1984
ISSN: 0209-9683,1439-6912
DOI: 10.1007/bf02579141