OFFSET
1,1
COMMENTS
If multiples of 2, 3, 5 and 7 are not excluded, then terms like 21, 33, 65, 77, 105, 165, 231,... belong to the sequence. - Giovanni Resta, May 21 2013
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..2091 (terms < 10^12)
MATHEMATICA
qcm[n_, d_] := Block[{p, e}, {p, e} = Transpose@FactorInteger@n; Length[p] > 1 && Max[e] == 1 && d < Min[p] && And @@ IntegerQ /@ ((n - d)/(p - d))]; Select[Range[10^6], qcm[#, 9] &] (* Giovanni Resta, May 21 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved