{ "id": "0707.1496", "version": "v1", "published": "2007-07-10T17:02:47.000Z", "updated": "2007-07-10T17:02:47.000Z", "title": "Subsets of F_p^n without three term arithmetic progressions have several large Fourier coefficients", "authors": [ "Ernie Croot" ], "comment": "This is a preliminary draft. Later drafts will have more references and cleaner proofs", "categories": [ "math.CO", "math.NT" ], "abstract": "Suppose that f : F_p^n -> [0,1] has expected value t in [p^(-n/9),1] (so, the density t can be quite low!). Furthermore, suppose that support(f) has no three-term arithmetic progressions. Then, we develop non-trivial lower bounds for f_j, which is the jth largest Fourier coefficient of f. This result is similar in spirit to that appearing in an earlier paper [1] by the author; however, in that paper the focus was on the ``small'' Fourier coefficients, whereas here the focus is on the ``large'' Fourier coefficients. Furthermore, the proof in the present paper requires much more sophisticated arguments than those of that other paper.", "revisions": [ { "version": "v1", "updated": "2007-07-10T17:02:47.000Z" } ], "analyses": { "subjects": [ "05D99" ], "keywords": [ "large fourier coefficients", "jth largest fourier coefficient", "non-trivial lower bounds", "three-term arithmetic progressions", "quite low" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0707.1496C" } } }