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%I #9 Oct 15 2021 10:45:59
%S 1,2,3,4,5,8,7,8,9,16,11,16,13,16,16,16,17,32,19,32,24,32,23,32,25,32,
%T 27,32,29,32,31,32,36,64,36,64,37,64,48,64,41,64,43,64,48,64,47,64,49,
%U 64,54,64,53,64,60,64,64,64,59,64,61,64,64,64,72,128,67,128,72,128,71
%N Least p-smooth number not less n, where p is the smallest prime factor of n.
%C a(n)<=2^k for n<=2^k.
%C a(n)=n for n in A000961. - _Ivan Neretin_, Apr 30 2016
%H Ivan Neretin, <a href="/A080785/b080785.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SmoothNumber.html">Smooth Number</a>.
%t a[n_] := Module[{p, k}, p = FactorInteger[n][[1, 1]]; For[k = n, True, k++, If[FactorInteger[k][[-1, 1]] <= p, Return[k]]]];
%t Table[a[n], {n, 1, 100}] (* _Jean-François Alcover_, Oct 15 2021 *)
%Y Cf. A020639, A006530.
%Y Cf. A000079, A003586, A051037, A002473, A051038, A080197, A080681, A080682, A080683.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Mar 12 2003
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