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%I #18 Dec 07 2022 10:14:47
%S 1,3,5,6,11,12,13,14,15,17,18,19,20,21,22,23,24,25,26,28,43,44,45,46,
%T 47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,65,66,67,68,69,70,
%U 71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89
%N Positive integers expressible as a quotient of two terms of A014486.
%C It's easy to see that 2^i is not so expressible, for i >= 1. One can prove that, for example, 7 is not so expressible by considering the intervals in which terms of A014486 lie. Many numbers can be proved inexpressible by (for example) restricting numerator and denominator to be of even length, not of the form (10)*100(0|1)*, etc.
%e 3 is in the sequence since 228 = 11100100_2 is balanced and so is 3*228 = 684 = 1010101100_2.
%Y Cf. A014486.
%K nonn,base,more
%O 1,2
%A _Jeffrey Shallit_, Dec 03 2022