There is no (95, 40, 12, 20) strongly regular graph

The Strongly Regular (40, 12, 2, 4) Graphs

In a previous paper it was established that there are at least 27 non-isomorphic strongly regular (40, 12, 2, 4) graphs. Using a different and more efficient method we have re-investigated these graphs and have now been able to determine them all, and so complete the classification. We have discovered that there are precisely 28 non-isomorphic (40, 12, 2, 4) strongly regular graphs. The one tha...

On the Strongly Regular Graph of Parameters

In an attempt to find a strongly regular graph of parameters (99, 14, 1, 2) or to disprove its existence, we studied its possible substructure and constructions.

College Voice Vol. 95 No. 12

There is no universal countable pentagon-free graph

No countable C,-free graph contains every countable C,-free graph as a subgraph, for n 2 4. For n = 4, this was proved earlier by J. Pach.

There is no universal countable random-free graph

We consider embeddings between infinite graphs. In particular, We establish that there is no universal element in the class of countable graphs into which the random graph is not embeddable.