OFFSET
1,1
COMMENTS
This sequence is a self-inverse permutation of the natural numbers.
LINKS
FORMULA
EXAMPLE
The first terms of the sequence, alongside K and its ordinal transform, are:
n a(n) K(n) o(n)
-- ---- ---- ----
1 2 1 1
2 1 2 1
3 4 2 2
4 3 1 2
5 6 1 3
6 5 2 3
7 8 1 4
8 7 2 4
9 10 2 5
10 9 1 5
11 13 2 6
12 14 2 7
13 11 1 6
14 12 1 7
15 16 2 8
16 15 1 8
17 18 1 9
18 17 2 9
19 20 2 10
20 19 1 10
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jan 30 2019
STATUS
approved