Cospectral mates for generalized Johnson and Grassmann graphs. (English) Zbl 1525.05106
Summary: We provide three infinite families of graphs in the Johnson and Grassmann schemes that are not uniquely determined by their spectrum. We do so by constructing graphs that are cospectral but non-isomorphic to these graphs.
MSC:
| 05C50 | Graphs and linear algebra (matrices, eigenvalues, etc.) |
| 15A18 | Eigenvalues, singular values, and eigenvectors |
| 05C75 | Structural characterization of families of graphs |
Citations:
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