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A279537 Numbers of the form 2^i * 6^j * 30^k. 3

%I

%S 1,2,4,6,8,12,16,24,30,32,36,48,60,64,72,96,120,128,144,180,192,216,

%T 240,256,288,360,384,432,480,512,576,720,768,864,900,960,1024,1080,

%U 1152,1296,1440,1536,1728,1800,1920

%N Numbers of the form 2^i * 6^j * 30^k.

%H Charles R Greathouse IV, <a href="/A279537/b279537.txt">Table of n, a(n) for n = 1..10000</a>

%F Sum_{n>=1} 1/a(n) = 72/29. - _Amiram Eldar_, Feb 18 2021

%t mx = 6000; Take[ Sort[ Flatten[ Table[2^i*6^j*30^k, {i, 0, Log[2, mx]}, {j, 0, Log[6, mx]}, {k, 0, Log[30, mx]}]]], 60] (* _Robert G. Wilson v_, Dec 14 2016 *)

%o (PARI) list(lim)=my(v=List(),x,y); for(k=0,logint(lim\=1,30), y=30^k; for(j=0,logint(lim\y,6), x=y*6^j; while(x<=lim, listput(v,x); x<<=1))); Set(v)

%Y Intersection of A025487 and A051037.

%Y Cf. A025610.

%K nonn

%O 1,2

%A _Charles R Greathouse IV_, Dec 14 2016

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Last modified July 31 18:54 EDT 2021. Contains 346376 sequences. (Running on oeis4.)