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On nested split graphs whose second largest eigenvalue is less than 1. (English) Zbl 1194.05098
Summary: We determine all nested split graphs (i.e. graphs having no induced subgraphs equal to $2{K}_{2},{P}_{4}$ or ${C}_{4}$) having the second largest eigenvalue less than 1 and give some data and observations regarding obtained results.
##### MSC:
 05C50 Graphs and linear algebra
##### References:
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