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Least number k such that n*k has the fewest possible ones in its binary expansion.
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%I #8 Feb 10 2020 06:16:26

%S 1,1,1,1,1,1,1,1,1,1,3,1,5,1,1,1,1,1,27,1,1,3,3,1,41,5,19,1,565,1,1,1,

%T 1,1,1,1,7085,27,7,1,25,1,3,3,1,3,11,1,1,41,1,5,1266205,19,7,1,9,565,

%U 9099507,1,17602325,1,1,1,1,1,128207979,1,1,1,119,1,1,7085,1,27,5,7,13

%N Least number k such that n*k has the fewest possible ones in its binary expansion.

%C a(n)=1 indicates that n is a sturdy number (A125121); that is, no multiple of n has fewer ones than the binary expansion of n. A086342(n) gives the least possible number of ones in the binary expansion of a multiple of n. Compare with A143073.

%H T. D. Noe, <a href="/A143069/b143069.txt">Table of n, a(n) for n=1..1000</a>

%H Trevor Clokie et al., <a href="https://arxiv.org/abs/2002.02731">Computational Aspects of Sturdy and Flimsy Numbers</a>, arxiv preprint arXiv:2002.02731 [cs.DS], February 7 2020.

%K nonn

%O 1,11

%A _T. D. Noe_, Jul 22 2008