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Edge-transitive graphs of small order and the answer to a 1967 question by Folkman. (English) Zbl 1428.05326
Summary: In this paper, we introduce a method for finding all edge-transitive graphs of small order, using faithful representations of transitive permutation groups of small degree, and we explain how we used this method to find all edge-transitive graphs of order up to 47, and all bipartite edge-transitive graphs of order up to 63. We also give an answer to a question of J. Folkman [J. Comb. Theory 3, 215–232 (1967; Zbl 0158.42501)] about semi-symmetric graphs of large valency; in fact we show that for semi-symmetric graphs of order $$2n$$ and valency $$d$$, the ratio $$d/n$$ can be arbitrarily close to 1.
##### MSC:
 05E18 Group actions on combinatorial structures 05C25 Graphs and abstract algebra (groups, rings, fields, etc.) 20B25 Finite automorphism groups of algebraic, geometric, or combinatorial structures 20C30 Representations of finite symmetric groups
Magma
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