OFFSET
1,1
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