OFFSET
1,2
COMMENTS
The sequence o corresponds to the ordinal transform of the sequence a.
This sequence has a taste of Fibonacci, as each pair of consecutive terms gives rise to the next term.
This sequence is unbounded:
- if the sequence was bounded, say a(n) <= M for any n > 0, then some value in the range 1..M, say t, would appear at least M times among the first M^2 terms, and we would have a value > M after the M-th occurrence of t, a contradiction.
This sequence has interesting graphical features (see Links section).
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..10000
Rémy Sigrist, Density plot of the first 10000000 terms
EXAMPLE
The first terms, alongside o, are:
n a(n) o(n)
-- ---- ----
1 1 1
2 2 1
3 2 2
4 3 1
5 3 2
6 3 3
7 5 1
8 4 1
9 2 3
10 4 2
11 5 2
12 4 3
13 5 3
14 6 1
15 4 4
16 5 4
17 8 1
18 5 5
19 6 2
20 7 1
PROG
(PARI) o = vector(18); for (n=1, 79, if (n<=2, v=n, v=pp+p); print1 (v ", "); [pp, p]=[p, o[1+v]++])
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jan 31 2019
STATUS
approved