PUBLICATIONS DE L'INSTITUT MATHEMATIQUE (BEOGRAD) (N.S.) Vol. 79(93), pp. 19–27 (2006) 

SOME TREES CHARACTERIZED BY EIGENVALUES AND ANGLESDragan Stevanovic and Vladimir BrankovPrirodnomatematicki fakultet, 18000 Nis, Serbia and Matematicki institut SANU, Kneza Mihaila 35, 11000 Beograd, SerbiaAbstract: A vertex of a simple graph is called large if its degree is at least 3. It was shown recently that in the class of starlike trees, which have one large vertex, there are no pairs of cospectral trees. However, already in the classes of trees with two or three large vertices there exist pairs of cospectral trees. Thus, one needs to employ additional graph invariant in order to characterize such trees. Here we show that trees with two or three large vertices are characterized by their eigenvalues and angles. Classification (MSC2000): 05C50 Full text of the article: (for faster download, first choose a mirror)
Electronic fulltext finalized on: 10 Oct 2006. This page was last modified: 27 Oct 2006.
© 2006 Mathematical Institute of the Serbian Academy of Science and Arts
