OFFSET
1,1
COMMENTS
78=2*3*13; 2,3 and 13 are not safe prime numbers,...
MATHEMATICA
lst={}; Do[If[Plus@@Last/@FactorInteger[n]==3, a=Length[First/@FactorInteger[n]]; If[a==3, b=First/@FactorInteger[n]; c=b[[1]]; d=b[[2]]; e=b[[3]]; If[ !PrimeQ[(c-1)/2]&&!PrimeQ[(d-1)/2]&&!PrimeQ[(e-1)/2], AppendTo[lst, n]]]], {n, 7!}]; lst
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Feb 27 2009
STATUS
approved