On Certain Integral Schreier Graphs of the Symmetric Group
نویسندگان
چکیده
منابع مشابه
On Certain Integral Schreier Graphs of the Symmetric Group
We compute the spectrum of the Schreier graph of the symmetric group Sn corresponding to the Young subgroup S2 × Sn−2 and the generating set consisting of initial reversals. In particular, we show that this spectrum is integral and for n ≥ 8 consists precisely of the integers {0, 1, . . . , n}. This implies that these graphs form a family of expanders (with unbounded degree).
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2007
ISSN: 1077-8926
DOI: 10.37236/961