%I
%S 1,2,3,2,5,3,2,3,5,3,5,2,3,5,3,5,3,5,2,3,5,5,3,5,3,5,2,3,5,5,3,5,3,5,
%T 3,5,5,2,5,3,5,5,3,5,3,5,3,5,5,3,5,2,5,3,5,5,3,5,5,3,5,5,3,5,5,3,5,2,
%U 5,3,5,5,5,3,5,5,3,5,3,5,5,3,5,5,3,5,2,5,5,3,5,5,5,5,3,5,5,3,5,3,5,5,3,5,5
%N Greatest prime factor of nth 5smooth number.
%C a(n) = A006530(A051037(n));
%C A112763(n) <= a(n) <= 5.
%t Reap[Do[p = FactorInteger[n][[1, 1]]; If[p < 7, Sow[p]], {n, 1, 2000}] ][[2, 1]] (* _JeanFrançois Alcover_, Dec 17 2017 *)
%Y Cf. A112756, A086411.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 18 2005
