A simple graph whose automorphism group is a cyclic group may be termed a cyclic group graph. The smallest nontrivial cyclic group graphs have nine nodes. There are a total of four graphs on nine nodes whose automorphism group is isomorphic to the cyclic group C3, illustrated above. The leftmost graph has the smallest number of edges and was illustrated by Harary (1994, p. 170), the second graph from the left is the graph obtained from the -configuration, the third is that configuration's graph complement, and the fourth is the complement of the first.
Other graphs whose automorphism groups are isomorphic to the cyclic group C3 include three of the Paulus graphs (each on 26 vertices), the 12th fullerene graph on 40 vertices, and Tutte's graph (on 46 vertices).
The smallest simple cyclic group C4 graphs have 10 vertices. The 12 such graphs are illustrated above. The cyclic group graph with 20 edges, which is not the smallest possible), is shown Fig. 4.8 in Arlinghaus (1985).
The -caveman graph is a group graph. The following table summarizes some other cyclic group graphs, where indicates a group graph and is the vertex count.
graph | ||
3 | 9 | configuration graph |
3 | 24 | Markström graph |
3 | 25 | two 25-Paulus graphs |
3 | 26 | one 26-Paulus graph (and its complement) |
3 | 29 | ten strongly regular graphs with parameters |
3 | 40 | one 40-fullerene |
3 | 40 | one strongly regular graph with parameters |
3 | 46 | Tutte's graph |
3 | 46 | two 46-fullerenes |
3 | 50 | two 50-fullerenes |
4 | 12 | Nauru configuration graph |
5 | 15 | Cremona-Richmond configuration graph |
5 | 35 | Johnson skeleton graph 47 |
5 | 40 | 40-O'Donnell graph |
5 | 45 | Hochberg-O'Donnell star graph |
5 | 50 | Watkins snark |
5 | 210 | Descartes snark |
6 | 25 | Golomb-Moser graph |
7 | 28 | Coxeter configuration graph |
9 | 40 | two strongly regular graphs with parameters |
12 | 48 | Berman configuration graph |
53 | 212 | regular nonplanar graph of degree 5 with diameter 4 |
99 | 198 | regular nonplanar graph of degree 16 with diameter 2 |