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%I #7 Oct 14 2019 14:04:37
%S 1,2,3,4,5,6,8,8,9,10,12,12,15,15,15,16,18,18,20,20,24,24,24,24,25,27,
%T 27,30,30,30,32,32,36,36,36,36,40,40,40,40,45,45,45,45,45,48,48,48,50,
%U 50,54,54,54,54,60,60,60,60,60,60,64,64,64,64,72,72,72,72,72
%N a(n) = smallest integer >= n which has only prime factors 2, 3 and 5.
%C This group of sequences is useful when looking for a number >= n to use as the basis for a Fast Fourier Transform when you have n data points.
%H Harvey P. Dale, <a href="/A130916/b130916.txt">Table of n, a(n) for n = 1..1000</a>
%t si[n_]:=Module[{k=n},While[Max[FactorInteger[k][[All,1]]]>5,k++];k]; Array[ si,70] (* _Harvey P. Dale_, Oct 14 2019 *)
%o (R) f <- function(n) nextn(n, factors = c(2,3,5))
%o a <- matrix(1:256,ncol=1)
%o apply(a,1,f)
%Y Cf. A134361, A151969, A151970.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Aug 23 2009
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