A015805 Numbers k such that phi(k) + 12 | sigma(k).

24, 38, 42, 54, 60, 70, 92, 114, 154, 168, 182, 238, 266, 315, 322, 378, 406, 434, 504, 518, 574, 602, 630, 658, 742, 760, 826, 854, 858, 938, 950, 994, 1022, 1080, 1106, 1162, 1246, 1350, 1358, 1414, 1442, 1498, 1526, 1582, 1778, 1820, 1834

Offset: 1

Author

Robert G. Wilson v

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Programs

Mathematica

Select[Range[10000], Divisible[DivisorSigma[1, #], EulerPhi[#] + 12] &] (* David Nacin, Mar 01 2012 *)

Extensions

Offset changed from 0 to 1 by Vincenzo Librandi, Mar 06 2012