cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A143073 Least number k such that the binary expansion of n*k has fewer ones than n, or 0 if no such k exists.

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%I A143073 #4 Mar 30 2012 17:22:50
%S A143073 0,0,0,0,0,0,0,0,0,0,3,0,5,0,0,0,0,0,27,0,0,3,3,0,41,5,3,0,5,0,0,0,0,
%T A143073 0,0,0,7085,27,7,0,25,0,3,3,0,3,3,0,0,41,0,5,5,3,3,0,9,5,3,0,5,0,0,0,
%U A143073 0,0,128207979,0,0,0,119,0,0,7085,0,27,5,7,7,0,1657009,25,395,0,0,3,3,3,0,0
%N A143073 Least number k such that the binary expansion of n*k has fewer ones than n, or 0 if no such k exists.
%C A143073 a(n)=0 indicates that n is a sturdy number (A125121); that is, no multiple of n has fewer ones than the binary expansion of n. If a(n)>0, n is a flimsy number (A005360). Compare with A143069.
%H A143073 T. D. Noe, <a href="/A143073/b143073.txt">Table of n, a(n) for n=1..1000</a>
%K A143073 nonn
%O A143073 1,11
%A A143073 _T. D. Noe_, Jul 22 2008