On Isomorphisms of Marušič–Scapellato Graphs

Autor: Ted Dobson
Rok vydání: 2015
Předmět:
Zdroj: Graphs and Combinatorics. 32:913-921
ISSN: 1435-5914
0911-0119
DOI: 10.1007/s00373-015-1640-4
Popis: Marusia?---Scapellato graphs are vertex-transitive graphs of order $$m(2^k + 1)$$m(2k+1), where m divides $$2^k - 1$$2k-1, whose automorphism group contains an imprimitive subgroup that is a quasiprimitive representation of $$\mathrm{SL}(2,2^k)$$SL(2,2k) of degree $$m(2^k + 1)$$m(2k+1). We show that any two Marusia?---Scapellato graphs of order pq, where p is a Fermat prime, and q is a prime divisor of $$p - 2$$p-2, are isomorphic if and only if they are isomorphic by a natural isomorphism derived from an automorphism of $$\mathrm{SL}(2,2^k)$$SL(2,2k). This work is a contribution towards the full characterization of vertex-transitive graphs of order a product of two distinct primes.
Databáze: OpenAIRE