Characterization of quasi-symmetric designs with eigenvalues of their block graphs
نویسندگان
چکیده
A quasi-symmetric design (QSD) is a (v, k, λ) design with two intersection numbers x, y, where 0 ≤ x < y < k. The block graph of a QSD is a strongly regular graph (SRG), whereas the converse is not true. Using Neumaier’s classification of SRGs related to the smallest eigenvalue, a complete parametric classification of QSDs whose block graph is an SRG with smallest eigenvalue −3, or second largest eigenvalue 2, is obtained.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 68 شماره
صفحات -
تاریخ انتشار 2017