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%I #14 Sep 21 2019 06:55:46
%S 12,18,20,24,36,40,48,54,56,60,72,80,84,88,90,96,100,104,108,112,120,
%T 126,132,140,144,150,156,160,162,168,176,180,192,196,198,200,204,208,
%U 216,220,224,228,234,240,252,260,264,270,272,276,280,288,294,300,304
%N Nonsquarefree abundant numbers.
%H Amiram Eldar, <a href="/A087245/b087245.txt">Table of n, a(n) for n = 1..10000</a>
%e m = 20 = 2*2*5 and sigma(20) = 42 > 2m = 40.
%t aQ[n_] := !SquareFreeQ[n] && DivisorSigma[1, n] > 2n; Select[Range[300], aQ] (* _Amiram Eldar_, Sep 21 2019 *)
%o (PARI) isok(n) = !issquarefree(n) && (sigma(n) > 2*n); \\ _Michel Marcus_, Sep 21 2019
%Y Cf. A087244-A087247, A008683, A000203, A013929, A005117, A005100, A005101.
%K nonn
%O 1,1
%A _Labos Elemer_, Sep 05 2003
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