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%I #23 Dec 04 2019 03:54:20
%S 27720,30240,32760,50400,55440,60480,65520,75600,83160,85680,90720,
%T 95760,98280,100800,105840,110880,115920,120120,120960,128520,131040,
%U 138600,141120,143640,151200,163800,166320,171360,176400,180180,181440,184800
%N Numbers k such that sigma(k) >= 4*k.
%C Called 4-abundant numbers. The first odd number is A119240(4) = 1853070540093840001956842537745897243375. - _T. D. Noe_, Mar 31 2011
%D Melvyn B. Nathanson, Elementary Methods in Number Theory, Springer, 2000, p 260.
%H Amiram Eldar, <a href="/A023198/b023198.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from T. D. Noe)
%t Select[Range[1000000], DivisorSigma[1, #] >= 4*#&] (* _Vladimir Joseph Stephan Orlovsky_, Apr 21 2010 *)
%Y Union of A027687 and A068404.
%K nonn
%O 1,1
%A _David W. Wilson_
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