A261255 Where MU-numbers (cf. A007335) occur in A003586 (3-smooth numbers).

2, 3, 5, 8, 10, 11, 15, 16, 20, 24, 25, 26, 31, 33, 38, 39, 44, 45, 47, 53, 54, 57, 61, 64, 70, 71, 72, 75, 80, 83, 87, 90, 92, 96, 101, 104, 105, 109, 113, 115, 119, 123, 125, 129, 134, 138, 140, 144, 145, 149, 151, 156, 161, 165, 166, 168, 173, 178, 180

Offset: 1

Author

Reinhard Zumkeller, Aug 13 2015

Keywords

• nonn

Examples

			.   n |   A007335(n)     | a(n) | A003586(a(n))
.  ---+------+-----------+------+--------------
.   1 |    2 |         2 |    2 |            2
.   2 |    3 |         3 |    3 |            3
.   3 |    6 |     2 * 3 |    5 |            6
.   4 |   12 |   2^2 * 3 |    8 |           12
.   5 |   18 |   2 * 3^2 |   10 |           18
.   6 |   24 |   2^3 * 3 |   11 |           24
.   7 |   48 |   2^4 * 3 |   15 |           48
.   8 |   54 |   2 * 3^3 |   16 |           54
.   9 |   96 |   2^5 * 3 |   20 |           96
.  10 |  162 |   2 * 3^4 |   24 |          162
.  11 |  192 |   2^6 * 3 |   25 |          192
.  12 |  216 | 2^3 * 3^3 |   26 |          216 .
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A007335, A003586.

Programs

Haskell

import Data.List (findIndex); import Data.Maybe (fromJust)
a261255 n = fromJust (findIndex (== a007335 n) a003586_list) + 1

Formula

A007335(n) = A003586(a(n)).