# a 7 Integers 11 ( 2011 )
نویسندگان
چکیده
Independently, Pirillo and Varricchio, Halbeisen and Hungerbühler and Freedman considered the following problem, open since 1992: Does there exist an infinite word w over a finite subset of Z such that w contains no two consecutive blocks of the same length and sum? We consider some variations on this problem in the light of van der Waerden’s theorem on arithmetic progressions.
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