Star number and star arboricity of a complete multigraph
نویسندگان
چکیده
منابع مشابه
Star arboricity
A star forest is a forest all of whose components are stars. The star arboricity, st(G) of a graph G is the minimum number of star forests whose union covers all the edges of G. The arboricity, A(G), of a graph G is the minimum number of forests whose union covers all the edges of G. Clearly st(G) > A(G). In fact, Algor and Alon have given examples which show that in some cases st(G) can be as ...
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Two inequalities are established connecting the graph invariants of incidence chromatic number, star arboricity and domination number. Using these, upper and lower bounds are deduced for the incidence chromatic number of a graph and further reductions are made to the upper bound for a planar graph. It is shown that cubic graphs with orders not divisible by four are not 4-incidence colorable. Sh...
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A hypercube Qn is a graph in which the vertices are all binary vectors of length n, and two vertices are adjacent if and only if their components differ in exactly one place. A galaxy or a star forest is a union of vertex disjoint stars. The star arboricity of a graph G, sa(G), is the minimum number of galaxies which partition the edge set of G. In this paper among other results, we determine t...
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 2006
ISSN: 0011-4642,1572-9141
DOI: 10.1007/s10587-006-0071-z