A352760 Lexigraphically earliest sequence of distinct nonnegative integers such that for any n >= 0, among the ternary digits of n and a(n) (counted with multiplicity) there are as many 1's as 2's.

0, 2, 1, 6, 8, 5, 3, 7, 4, 17, 20, 11, 24, 26, 18, 15, 23, 9, 14, 19, 10, 21, 25, 16, 12, 22, 13, 35, 53, 29, 56, 62, 47, 33, 51, 27, 60, 74, 54, 78, 80, 71, 59, 72, 44, 45, 61, 32, 65, 77, 50, 34, 52, 28, 38, 55, 30, 57, 69, 42, 36, 46, 31, 63, 73, 48, 75, 79

Offset: 0

Author

Rémy Sigrist, Jul 05 2022

Keywords

• nonn
• base

Comments

This sequence is a self-inverse permutation of the nonnegative integers.

Examples

			The first terms, alongside their ternary expansions, are:
  n   a(n)  ter(n)  ter(a(n))
  --  ----  ------  ---------
   0     0       0          0
   1     2       1          2
   2     1       2          1
   3     6      10         20
   4     8      11         22
   5     5      12         12
   6     3      20         10
   7     7      21         21
   8     4      22         11
   9    17     100        122
  10    20     101        202
  11    11     102        102
  12    24     110        220
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..6560
• Rémy Sigrist, PARI program
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

Cf. A004488, A039001 (fixed points), A331275, A355504.

Programs

PARI

See Links section.

Formula

a(n) = n iff n belongs to A039001.

a(n) < 3^k iff n < 3^k.