Abstract
The (isotropic) unitary graph \({U \left(n, q^{2}\right)}\) is introduced. When n = 2 or 3, \({U \left(2, q^{2}\right)}\) or \({U \left(3, q^{2}\right)}\) are complete graphs with q + 1 or q 3 + 1 vertices, respectively. When n ≥ 4, it is shown that \({U \left(n, q^{2}\right)}\) is strongly regular and its parameters are computed. The group of graph automorphisms of \({U \left(n, q^{2}\right)}\) , when n ≠ 4, 5, is determined.
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Supported by the National Natural Science Foundation of China and KLMM.
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Wan, ZX., Zhou, K. Unitary Graphs and Their Automorphisms. Ann. Comb. 14, 367–395 (2010). https://doi.org/10.1007/s00026-010-0065-2
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DOI: https://doi.org/10.1007/s00026-010-0065-2