Subgraphs with prescribed valencies
نویسندگان
چکیده
منابع مشابه
Spanning subgraphs with specified valencies
The author has published a necessary and sufficient condition for a fmite loopless graph to have a spanning subgraph with a specified positive valency at each vertex (see [8,9). In the present paper it is contended that the condition can be made more useful as a tool of graph theory by imposing a maximality condition. 1. The condition for an I-factor Let G be a finite graph. Loops and multiple ...
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Dom de Caen posed the question whether connected graphs with three distinct eigenvalues have at most three distinct valencies. We do not answer this question, but instead construct connected graphs with four and five distinct eigenvalues and arbitrarily many distinct valencies. The graphs with four distinct eigenvalues come from regular two-graphs. As a side result, we characterize the disconne...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory
سال: 1970
ISSN: 0021-9800
DOI: 10.1016/s0021-9800(70)80033-3