A124509 Range of A124508.

1, 6, 12, 24, 36, 48, 72, 96, 144, 192, 216, 288, 384, 432, 576, 768, 864, 1152, 1296, 1536, 1728, 2304, 2592, 3072, 3456, 4608, 5184, 6144, 6912, 7776, 9216, 10368, 12288, 13824, 15552, 18432, 20736, 24576, 27648, 31104, 36864, 41472, 46656, 49152, 55296, 62208

Offset: 1

Author

Reinhard Zumkeller, Nov 04 2006

Keywords

• nonn
• easy

Comments

1 together with numbers of the form 2^i * 3^j with i >= j >= 1. - Amiram Eldar, Jul 11 2023

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Smooth Number.

Crossrefs

Subsequence of A003586.

A007283 is a subsequence.

Cf. A124508, A124510.

Programs

Mathematica

With[{max = 70000}, Join[{1}, Sort[Flatten[Table[2^i*3^j, {i, 1, Log2[max]}, {j, 1, Min[i, Log[3, max/2^i]]}]]]]] (* Amiram Eldar, Jul 11 2023 *)

Formula

a(n) = A124508(A124510(n)).

Sum_{n>=1} 1/a(n) = 7/5. - Amiram Eldar, Jul 11 2023

Extensions

Missing term a(43) inserted and more terms added by Amiram Eldar, Jul 11 2023