Croatica Chemica Acta, Vol. 81 No. 2, 2008.
Short communication, Note
Minimal Spectrum-Sums of Bipartite Graphs with Exactly Two Vertex-Disjoint Cycles
Fuyi Wei
; Department of Applied Mathematics, College of Science, South China Agricultural University, Guangzhou, China
Bo Zhou
orcid.org/0000-0001-7321-9554
; Department of Mathematics, South China Normal University, Guangzhou, P. R. China
Nenad Trinajstić
; Ruđer Bošković Institute, Zagreb, Croatia
Abstract
The spectrum-sum of a graph is defined as the sum of the absolute values of its eigenvalues.
The graphs with minimal spectrum-sums in the class of connected bipartite graphs with exactly
two vertex-disjoint cycles, in the class of connected bipartite graphs with exactly two vertex-
-disjoint cycles whose lengths are congruent with 2 modulo 4, and in the class of connected bipartite
graphs with exactly two vertex-disjoint cycles one of which has length congruent with 2
modulo 4, are determined, respectively.
Keywords
graph spectrum; spectrum-sum; bipartite graphs; alternant structures
Hrčak ID:
28505
URI
Publication date:
30.6.2008.
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