On the Spectral Moment of Graphs with given Clique Number
نویسندگان
چکیده
Let Ln,t be the set of all n-vertex connected graphs with clique number t (2 ≤ t ≤ n). For nvertex connected graphs with given clique number, lexicographic ordering by spectral moments (S-order) is discussed in this paper. The first ∑⌊(n−t−1)/3⌋ i=1 (n − t − 3i) + 1 graphs with 3 ≤ t ≤ n − 4, and the last few graphs, in the Sorder, among Ln,t are characterized. In addition, all graphs in Ln,n ∪ Ln,n−1 have an S-order; for the cases t = n − 2 and t = n− 3, the first three and the first seven graphs in the set Ln,t are characterized, respectively.
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