| Double-star snark | |
| Vertices: | 30 |
| Edges: | 45 |
| Diameter: | 4 |
| Radius: | 4 |
| Girth: | 6 |
| Automorphisms: | 80 |
| Chromatic Number: | 3 |
| Chromatic Index: | 4 |
| Properties: | Snark Hypohamiltonian |
| Book Thickness: | 3 |
| Queue Number: | 2 |
In the mathematical field of graph theory, the double-star snark is a snark with 30 vertices and 45 edges.
In 1975, Rufus Isaacs introduced two infinite families of snarks—the flower snark and the BDS snark, a family that includes the two Blanuša snarks, the Descartes snark and the Szekeres snark (BDS stands for Blanuša Descartes Szekeres). Isaacs also discovered one 30-vertex snark that does not belong to the BDS family and that is not a flower snark — the double-star snark.
As a snark, the double-star graph is a connected, bridgeless cubic graph with chromatic index equal to 4. The double-star snark is non-planar and non-hamiltonian but is hypohamiltonian. It has book thickness 3 and queue number 2.[1]