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%I #17 Feb 18 2021 02:32:44
%S 1,2,4,6,8,12,16,24,30,32,36,48,60,64,72,96,120,128,144,180,192,210,
%T 216,240,256,288,360,384,420,432,480,512,576,720,768,840,864,900,960,
%U 1024,1080,1152,1260,1296,1440,1536,1680,1728,1800,1920,2048,2160,2304,2520,2592
%N Numbers of the form 2^i * 6^j * 30^k * 210^m where i, j, k, m >= 0.
%H Amiram Eldar, <a href="/A333964/b333964.txt">Table of n, a(n) for n = 1..10000</a>
%F Sum_{n>=1} 1/a(n) = 15120/6061. - _Amiram Eldar_, Feb 18 2021
%t mx = 2600; Select[Sort[Flatten[Table[2^i*6^j*30^k*210^m, {i, 0, Log[2, mx]}, {j, 0, Log[6, mx]}, {k, 0, Log[30, mx]}, {m, 0, Log[210, mx]}]]], # <= mx &] (* _Amiram Eldar_, Apr 24 2020 after _Robert G. Wilson v_ at A279537 *)
%Y Intersection of A025487 and A002473.
%Y Cf. A025610, A279537.
%K nonn
%O 1,2
%A _David A. Corneth_, Apr 20 2020
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