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%I #6 Mar 12 2016 21:56:31
%S 1,2,4,5,9,9,11,11,11,11,13,13,19,19,19,19,19,19,25,25,29,29,29,29,29,
%T 29,29,29,37,37,37,37,37,37,37,37,53,53,53,53,53,53,53,53,53,53,53,53,
%U 53,53,53,53,59,59,59,59,59,59,61,61,67,67,67,67,67,67,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,101
%N Discriminator sequence for the powers of 2: smallest positive integer d such that 2^0, 2^1, ..., 2^{n-1} are all incongruent modulo d.
%C The discriminator of a finite sequence s is the smallest positive integer d such that all the elements of s are incongruent modulo d. The sequence in question is the discriminator of the first n powers of 2.
%H Zhi-Wei Sun, <a href="http://dx.doi.org/10.1016/j.jnt.2013.02.003">On functions taking only prime values</a>, J. Number Theory 133(2013), no.8, 2794-2812.
%K nonn
%O 0,2
%A _Jeffrey Shallit_, Mar 11 2016