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%I #11 Aug 14 2021 02:16:36
%S 1,28,40,117,135,196,200,224,496,640,775,819,891,1000,1372,1521,1550,
%T 1568,1701,1792,2176,2325,2480,3100,3159,3200,3375,3724,4455,5000,
%U 5632,5733,6200,6860,6875,6975,8128,9604,10240,10880,10935,10976,11907
%N Numbers k that divide sigma(k) * phi(k) and are not divisible by 6.
%D George E. Andrews, "Number Theory," Dover Books, NY, 1971, Page 84.
%t Do[ If[ Mod[ n, 6 ]!=0, If[ Mod[ DivisorSigma[ 1, n ]*EulerPhi[ n ], n ]==0, Print[ n ] ] ], {n, 1, 25000} ]
%Y Cf. A011775.
%K easy,nonn
%O 1,2
%A _Robert G. Wilson v_, Jul 22 2000
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