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%I #14 Sep 08 2022 08:45:23
%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 the n-th 5-smooth number.
%H Amiram Eldar, <a href="/A112764/b112764.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A006530(A051037(n));
%F A112763(n) <= a(n) <= 5.
%t Reap[Do[p = FactorInteger[n][[-1, 1]]; If[p < 7, Sow[p]], {n, 1, 2000}] ][[2, 1]] (* _Jean-François Alcover_, Dec 17 2017 *)
%o (Magma) [1] cat [Max(PrimeDivisors(k)): k in [2..1500]| PrimeDivisors(k) subset [2, 3, 5]]; // _Marius A. Burtea_, Feb 07 2020
%Y Cf. A051037, A006530, A086411, A112756, A112763.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 18 2005
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