OFFSET
1,1
MATHEMATICA
nn=10000; p=Select[Union[Flatten[Table[d=DivisorSigma[0, n]; {n-d, n+d}, {n, nn}]]], PrimeQ]; Complement[Prime[Range[PrimePi[p[[-1]]]]], p]
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Nov 21 2010
EXTENSIONS
Extended and corrected by T. D. Noe, Nov 21 2010
STATUS
approved