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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.

A344585 Numbers whose sum of proper divisors (A001065) is greater than their arithmetic derivative (A003415).

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%I A344585 #10 Jun 07 2021 21:05:04
%S A344585 6,10,14,15,21,22,26,30,33,34,35,38,39,42,46,51,55,57,58,60,62,65,66,
%T A344585 69,70,74,77,78,82,84,85,86,87,90,91,93,94,95,102,105,106,110,111,114,
%U A344585 115,118,119,122,123,126,129,130,132,133,134,138,140,141,142,143,145,146,150,154,155,156,158,159,161,165,166,170
%N A344585 Numbers whose sum of proper divisors (A001065) is greater than their arithmetic derivative (A003415).
%C A344585 Differs from A212168 for the first time at n=100, where a(100) = 221, while A212168(100) = 220. See also comments in A211991.
%H A344585 Antti Karttunen, <a href="/A344585/b344585.txt">Table of n, a(n) for n = 1..20000</a>
%o A344585 (PARI)
%o A344585 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A344585 isA344585(n) = (A003415(n) < (sigma(n)-n));
%Y A344585 Cf. A001065, A003415, A212168, A344586 (complement).
%Y A344585 Positions of negative terms in A211991.
%K A344585 nonn
%O A344585 1,1
%A A344585 _Antti Karttunen_, May 24 2021