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%I #21 Sep 09 2019 01:23:35
%S 1,2,6,9,10,16,18,22,28,30,33,42,64,65,71,72,82,87,90,114,130,136,156,
%T 182,198,208,215,280,294,336,380,390,403,451,616,660,683,755,777,964,
%U 990,1168,1260,1267,1330,1342,1348,1480,1638,1744,1953,2025,2074,2088
%N Numbers k such that phi(k) | sigma(k + 5).
%H Ivan Neretin, <a href="/A015843/b015843.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[3000], Divisible[DivisorSigma[1, 5 + #], EulerPhi[#]] &] (* _David Nacin_, Mar 03 2012 *)
%o (PARI) isok(n) = !(sigma(n+5) % eulerphi(n)); \\ _Michel Marcus_, Feb 05 2017
%K nonn
%O 1,2
%A _Robert G. Wilson v_
%E a(1) = 1 inserted by _Ivan Neretin_, Feb 05 2017
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