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%I #19 Sep 08 2022 08:44:40
%S 5,10,14,22,34,35,38,58,70,82,95,110,118,140,142,143,191,202,214,224,
%T 230,274,298,308,358,374,376,382,394,454,478,538,562,590,598,616,620,
%U 622,623,694,728,838,862,920,922,1012,1042,1121,1138,1198
%N Numbers k such that phi(k + 4) | sigma(k) for k not congruent to 0 (mod 3).
%H G. C. Greubel, <a href="/A015847/b015847.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[1000], Mod[#, 3] > 0 && Divisible[DivisorSigma[1,#], EulerPhi[#+4]] &] (* _Amiram Eldar_, Dec 13 2018 *)
%o (PARI) is(n)=n%3 && !(sigma(n)%eulerphi(n+4)) \\ _Charles R Greathouse IV_, Sep 25 2012
%o (Magma) [n: n in [1..1000] | n mod 3 ne 0 and DivisorSigma(1,n) mod EulerPhi(n+4) eq 0]; // _G. C. Greubel_, Dec 13 2018
%Y Subsequence of A015820.
%K nonn
%O 1,1
%A _Robert G. Wilson v_
%E Title and PARI program corrected by _Sean A. Irvine_, Dec 13 2018
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