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%I #19 Sep 08 2019 17:38:13
%S 10,20,26,58,122,1018,1040,2042,8186,32762,522752,2097146,8388602,
%T 9898496,16871744,33554426,1073741818,1630145024
%N Numbers k such that phi(k + 6) | sigma(k) + 6.
%C a(19) > 10^12. - _Donovan Johnson_, Feb 28 2012
%t Select[Range[100000],
%t Divisible[DivisorSigma[1, #] + 6, EulerPhi[# + 6]] &] (* _David Nacin_, Feb 2012 *)
%K nonn
%O 1,1
%A _Robert G. Wilson v_
%E Offset corrected and a(10)-a(18) from _Donovan Johnson_, Feb 28 2012