Tidier Examples for Lower Bounds on Diagonal Ramsey Numbers

There is a family (Hk) of graphs such thatHkhas order[formula]but has no clique or stable set of orderk. This result of Spencer provides the best known lower bound for the diagonal Ramsey numbersR(k, k). Here we see that the graphsHkcan be taken to be regular, self-complementary, and pseudo-random.