Let Forb(G) denote the class of graphs with countable vertex sets which do not contain G as a subgraph. If G is finite, 2-connected, but not complete, then Forb(G) has no element which contains every other element of Forb(G) as a subgraph, i.e., this class contains no universal graph.
✦ LIBER ✦
On the Existence of Free Structures over Universal Classes
✍ Scribed by George Grätzer
- Publisher
- John Wiley and Sons
- Year
- 1968
- Tongue
- English
- Weight
- 291 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0025-584X
No coin nor oath required. For personal study only.
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