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A073721
Remainder of division Sigma[n]/PrimePi[n] equals zero.
1
2, 3, 5, 6, 7, 14, 15, 21, 29, 38, 44, 57, 66, 78, 92, 94, 95, 106, 108, 114, 116, 118, 120, 133, 154, 174, 177, 182, 188, 232, 255, 300, 304, 305, 349, 351, 359, 413, 417, 418, 468, 488, 506, 526, 595, 615, 629, 688, 872, 945, 954, 1001, 1002, 1006, 1011, 1018
OFFSET
1,1
FORMULA
A000203(n)/A000720(n) is integer
MATHEMATICA
Do[s=Mod[DivisorSigma[1, n], PrimePi[n]]; If[s==0, Print[n]], {n, 1, 2500}]
Select[Range[2, 1200], Divisible[DivisorSigma[1, #], PrimePi[#]]&] (* Harvey P. Dale, Jan 31 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 05 2002
STATUS
approved