منابع مشابه
Frucht Graph is not Hyperenergetic
If 1 2 , ,..., p are the eigen values of a p-vertex graph , the energy of is G G 1 ( ) p i i E G . If , then is said to be hyperenergetic. We show that the Frucht graph, the graph used in the proof of well known Frucht’s theorem, is not hyperenergetic. Thus showing that every abstract group is isomorphic to the automorphism group of some non-hyperenergetic graph. AMS Mathematics S...
متن کاملBounds for the Hückel Energy of a Graph
Let G be a graph on n vertices with r := bn/2c and let λ1 ≥ · · · ≥ λn be adjacency eigenvalues of G. Then the Hückel energy of G, HE(G), is defined as HE(G) = ( 2 Pr i=1 λi, if n = 2r; 2 Pr i=1 λi + λr+1, if n = 2r + 1. The concept of Hückel energy was introduced by Coulson as it gives a good approximation for the π-electron energy of molecular graphs. We obtain two upper bounds and a lower bo...
متن کاملHyperenergetic Graphs and Cyclomatic Number
AMS Mathematics Subject Classification (2000): 05C50
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We consider embeddings between infinite graphs. In particular, We establish that there is no universal element in the class of countable graphs into which the random graph is not embeddable.
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ژورنال
عنوان ژورنال: Journal of the Serbian Chemical Society
سال: 2000
ISSN: 0352-5139,1820-7421
DOI: 10.2298/jsc0011799g