Dual polar spaces as extremal distance-regular graphs
نویسنده
چکیده
A new inequality for the parameters of distance-regular graphs is proved. It implies that if there are infinitely many distance-regular graphs with fixed λ,μ, ai and ci containing an induced quadrangle then necessarily ci+1 ≥ 1+(μ−1)ci . As the dual polar graphs show, this inequality is best possible. Some related results are also discussed. © 2003 Elsevier Ltd. All rights reserved.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 25 شماره
صفحات -
تاریخ انتشار 2004