Sets Whose Difference Set Is Square-free
نویسنده
چکیده
The purpose of this note is to give an exposition of the best-known bound on the density of sets whose difference set contains no squares which was first derived by Pintz, Steiger and Szemerédi in [PSS88]. We show how their method can be brought in line with the modern view of the energy increment strategy employed in problems such as Szemerédi’s Theorem on arithmetic progressions, and explore the extent to which the particularities of the method are specific to the set of squares.
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