A300889 a(n) is the least positive multiple of n which is a Fibbinary number (A003714).

1, 2, 9, 4, 5, 18, 21, 8, 9, 10, 33, 36, 65, 42, 165, 16, 17, 18, 133, 20, 21, 66, 69, 72, 325, 130, 81, 84, 145, 330, 341, 32, 33, 34, 1365, 36, 37, 266, 273, 40, 41, 42, 129, 132, 585, 138, 329, 144, 1029, 650, 1173, 260, 265, 162, 165, 168, 513, 290, 649

Offset: 1

Author

Rémy Sigrist, Mar 14 2018

Keywords

• nonn
• base

Examples

			The first terms, alongside their binary representation, are:
  n  a(n)    binary(a(n))
  -- ----    ------------
   1    1           1
   2    2          10
   3    9        1001
   4    4         100
   5    5         101
   6   18       10010
   7   21       10101
   8    8        1000
   9    9        1001
  10   10        1010
  11   33      100001
  12   36      100100
  13   65     1000001
  14   42      101010
  15  165    10100101
  16   16       10000
  17   17       10001
  18   18       10010
  19  133    10000101
  20   20       10100
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A003714, A300867.

Programs

PARI

a(n) = forstep (k=1, oo, 2, if (bitand(k*n, 2*k*n)==0, return (k*n)))

Formula

a(n) = n * A300867(n).

a(2*n) = 2*a(n).

a(n) = n iff n belongs to A003714.