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%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 n-th 5-smooth number.
%C a(n) = A006530(A051037(n));
%C A112763(n) <= a(n) <= 5.
%Y Cf. A112756, A086411.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 18 2005