Roth proved that for every d > 0 there exists an integer N(d) such that if the set of integers {1,2,..., N(d)} is partitioned into two subsets, then at least one of the subsets contains a three-term arithmetic progression. His proof used the circle method of Hardy-Littlewood-Vinogradov. The talk will give Roth's proof of the theorem.

Mel Nathanson