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%I #12 Aug 14 2019 08:25:47
%S 5040,7560,10080,12600,13860,15120,17640,18480,20160,21840,22680,
%T 25200,27720,30240,32760,35280,36960,37800,39600,40320,41580,42840,
%U 43680,45360,46200,47520,47880,49140,50400,51480,52920,54600,55440,56160
%N Numbers n such that sigma(n)^2 > 9*sigma_2(n) where sigma_2(n) is the sum of squares over the divisors of n.
%H Amiram Eldar, <a href="/A068378/b068378.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[60000],DivisorSigma[1,#]^2>9DivisorSigma[2,#]&] (* _Harvey P. Dale_, Mar 20 2015 *)
%o (PARI) for(n=1,1000,if(sigma(n)^2>9*sumdiv(n,k,k^2),print1(n,",")))
%Y Cf. A000203, A001157.
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, Apr 04 2002
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