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%I #18 Sep 09 2019 01:20:39
%S 1,2,3,4,5,6,7,8,12,16,20,22,24,26,27,28,31,35,39,40,50,58,63,70,88,
%T 95,108,112,116,120,135,152,163,183,224,228,241,273,315,323,364,369,
%U 455,476,520,524,616,620,632,703,782,855,903,945,950,1008,1124,1188
%N Numbers k such that phi(k) | sigma(k + 7).
%H Ivan Neretin, <a href="/A015845/b015845.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[3000], Divisible[DivisorSigma[1, 7 + #], EulerPhi[#]] &] (* _David Nacin_, Mar 03 2012 *)
%o (PARI) is(n)=!(sigma(n+7)%eulerphi(n)) \\ _Charles R Greathouse IV_, Sep 25 2012
%K nonn
%O 1,2
%A _Robert G. Wilson v_
%E a(1) = 1 inserted by _Ivan Neretin_, Feb 05 2017