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# Tag Archives: two-graph

## Primitive switching classes

Last year I wrote here about switching classes of graphs for which the switching class has a primitive automorphism group. (I repeat the definitions briefly below.) I conjectured that, except for the trivial switching classes of the complete and null … Continue reading

Posted in exposition, mathematics
Tagged Akos Seress, Don Taylor, Pablo Spiga, primitive group, switching class, two-graph
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## The Graph Extension Theorem

I made some notes on the Graph Extension Theorem for a new research project. They may be of wider interest, so here is a summary. Shult’s Graph Extension Theorem is a simple device for showing that certain permutation groups have … Continue reading

Posted in exposition
Tagged Higman, Seidel, Shult, switching, transitive extension, two-graph
4 Comments