### Top Posts

### Recent comments

- Ross Templeman on The economic crisis
- Peter Cameron on A symmetric design
- Peter Cameron on A symmetric design
- Peter Cameron on Across New Zealand
- Einar Steingrimsson on Across New Zealand

### Blogroll

- Annoying precision
- Astronomy Picture of the Day
- Azimuth
- Bad science
- Bob Walters
- Coffee, love, and matrix algebra
- Computational semigroup theory
- DC's Improbable Science
- Diamond Geezer
- Exploring East London
- Gödel's lost letter and P=NP
- Gil Kalai
- Haris Aziz
- Intersections
- Jane's London
- Jon Awbrey
- LMS blogs page
- Log24
- London Algebra Colloquium
- London Reconnections
- Machines like us
- Marie Cameron's blog
- MathBlogging
- Micromath
- Neill Cameron
- neverendingbooks
- Noncommutative geometry
- numericana hall of fame
- Paul Goldberg
- Robert A. Wilson's blog
- Sheila's blog
- Since it is not …
- Spitalfields life
- Stubborn mule
- SymOmega
- Terry Tao
- The De Morgan Journal
- The London column
- The Lumber Room
- The matroid union
- Theorem of the day
- Tim Gowers
- XKCD

### Find me on the web

### Cameron Counts: RSS feeds

### Meta

# 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
Leave a comment

## 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