“…This is the problem of obtaining constructive lower bounds for the usual diagonal Ramsey numbers. Specifically, we want to describe explicitly, for every k, a graph with c k nodes that contains neither a clique of size k, nor a stable set of size k, where c > 1 is a constant, independent of k. The best known result in this direction is that of Frankl and Wilson (1981), who constructed such a graph with exp Ω(log 2 k/ log log k) nodes. It may be true that for primes q, the Paley graphs G q are better examples, but, at present, a proof of this, which would have several new number-theoretic consequences, seems hopeless.…”