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%I #14 Dec 04 2013 05:06:54
%S 1,2,4,6,12,24,28,36,48,60,120,180,234,240,360,496,600,672,720,840,
%T 1170,1260,1680,1800,2016,2520,4200,5040,8128,10080,12600,15120,22320,
%U 25200,27000,27720,37800,55440,55800,55860,110880,138600,166320,167580,277200
%N Numbers n such that sigma(n)/n is equal to sigma(k)/k for some k being superabundant (A004394).
%C Previous name was: Numbers n such that sigma(k)/k < sigma(n)/n for k=1,2,3...,n-1.
%o (PARI) lista(nn) = {vs = Set(); maxs = 0; for(n = 1, nn, news = sigma(n, -1); if (news > maxs, maxs = news; print1(n, ", "); vs = Set(concat(vs, maxs));, if (setsearch(vs, news), print1(n, ", "));););} \\ _Michel Marcus_, Dec 02 2013
%Y Cf. A004394.
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Aug 23 2002
%E New name and more terms from _Michel Marcus_, Dec 02 2013
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