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A304881
Lexicographically earliest sequence of distinct positive terms such that for any n > 0, the 3-adic valuation of a(n) equals the 2-adic valuation of a(n+1).
3
1, 3, 2, 5, 7, 9, 4, 11, 13, 15, 6, 10, 17, 19, 21, 14, 23, 25, 27, 8, 29, 31, 33, 18, 12, 22, 35, 37, 39, 26, 41, 43, 45, 20, 47, 49, 51, 30, 34, 53, 55, 57, 38, 59, 61, 63, 28, 65, 67, 69, 42, 46, 71, 73, 75, 50, 77, 79, 81, 16, 83, 85, 87, 54, 24, 58, 89
OFFSET
1,2
COMMENTS
See A298196 for a similar sequence and additional comments.
This sequence is a permutation of the natural number, with inverse A304882.
The only known fixed point is a(1) = 1.
EXAMPLE
The first terms, alongside their 2-adic and 3-adic valuations, are:
n a(n) v2 v3
-- ---- -- --
1 1 0 0
2 3 0 1
3 2 1 0
4 5 0 0
5 7 0 0
6 9 0 2
7 4 2 0
8 11 0 0
9 13 0 0
10 15 0 1
11 6 1 1
12 10 1 0
13 17 0 0
14 19 0 0
15 21 0 1
16 14 1 0
17 23 0 0
18 25 0 0
19 27 0 3
20 8 3 0
CROSSREFS
Cf. A007814, A298196, A304882 (inverse).
Sequence in context: A151749 A175911 A337405 * A266635 A110338 A371221
KEYWORD
nonn
AUTHOR
Rémy Sigrist, May 20 2018
STATUS
approved