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%I #10 Feb 17 2024 10:32:47
%S 1,4,9,16,20,25,36,49,50,64,81,100,117,121,144,169,180,196,225,242,
%T 256,289,324,325,361,400,441,450,468,484,500,529,576,578,605,625,650,
%U 676,729,784,800,841,900,961,980,1024,1025,1058,1089,1156,1225,1280,1296
%N Sigma(1,n) divides Sigma(4,n).
%C sigma_1(n) is the sum of the divisors of n [same as sigma(n)] (A000203).
%C sigma_2(n) is the sum of the squares of the divisors of n (A001157).
%C sigma_4(n) is the sum of the 4th powers of the divisors of n (A001159).
%H Paolo P. Lava, <a href="/A046870/b046870.txt">Table of n, a(n) for n = 1..1000</a>
%e n=a(18)=196 of which divisor power sums for k=0,1,2,3,4 are 9,399,51471, 8613489, 1574446419. Sigma_1=399 and Sigma_4=51471*30589=399*129*30589. Thus Both Sigma_2 and Sigma_1 divide Sigma_4.
%Y Has large overlap with A020487.
%K nonn
%O 1,2
%A _Labos Elemer_
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