A355642 Lexicographically earliest sequence of distinct nonnegative integers such that for any n >= 0, the balanced ternary expansion of n * a(n) contains as many negative trits as positive trits.

0, 2, 1, 6, 4, 12, 3, 8, 7, 16, 13, 14, 5, 10, 11, 26, 9, 24, 23, 28, 20, 22, 21, 18, 17, 32, 15, 46, 19, 30, 29, 40, 25, 42, 34, 48, 36, 38, 37, 44, 31, 52, 33, 54, 39, 58, 27, 74, 35, 56, 55, 68, 41, 70, 43, 50, 49, 64, 45, 66, 60, 72, 63, 62, 57, 76, 59, 80

Offset: 0

Author

Rémy Sigrist, Jul 11 2022

Keywords

• nonn
• base

Comments

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

Examples

			The first terms, alongside the balanced ternary expansion of n * a(n), are:
  n   a(n)  bter(n*a(n))
  --  ----  ------------
   0     0             0
   1     2            1T
   2     1            1T
   3     6          1T00
   4     4          1TT1
   5    12         1T1T0
   6     3          1T00
   7     8         1T01T
   8     7         1T01T
   9    16        1TT100
  10    13        1TTT11
  11    14        1T0T01
  12     5         1T1T0
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..2187
• Rémy Sigrist, PARI program
• Index entries for sequences that are permutations of the natural numbers

Crossrefs

See A306993 for a similar sequence.

Cf. A065363, A174658, A355639.

Programs

PARI

See Links section.