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Numbers k such that phi(k) + 10 | sigma(k).
1

%I #19 Feb 12 2021 06:22:57

%S 6,12,30,68,96,264,368,2064,4240,4636,6588,7276,10272,11800,36600,

%T 188544,251648,415000,1296640,3113472,50202624,201068544,16097947360,

%U 17177182208,25876667904,85895741440

%N Numbers k such that phi(k) + 10 | sigma(k).

%C a(27) > 10^12. - _Donovan Johnson_, Feb 28 2012

%t Select[Range[1000000],Divisible[DivisorSigma[1,#],EulerPhi[#]+10]&] (* _Harvey P. Dale_, Jul 17 2011 *)

%Y Cf. A000010, A000203.

%K nonn

%O 1,1

%A _Robert G. Wilson v_

%E More terms from _Harvey P. Dale_, Jul 17 2011

%E Offset corrected and a(19)-a(26) from _Donovan Johnson_, Feb 28 2012