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%I #19 Sep 08 2019 19:29:13
%S 175,220,350,752,3772,4720,5092,15296,80320,269872,632752,807650,
%T 1126672,1304320,4176896,4386476,20945920,37030556,1073463296,
%U 17178755072,34796530432,85897707520,274873450496
%N Numbers k not congruent to 0 (mod 3) such that phi(k) + 4 | sigma(k).
%C a(24) > 10^12. - _Donovan Johnson_, Feb 28 2012
%t Select[Range[100000],
%t Divisible[DivisorSigma[1, #], EulerPhi[#] + 4] && !
%t Divisible[#, 3] &] (* _David Nacin_, Feb 28 2012 *)
%K nonn
%O 1,1
%A _Robert G. Wilson v_
%E Offset corrected and a(10)-a(23) from _Donovan Johnson_, Feb 28 2012