A336268 Lexicographically earliest sequence of positive integers such that for any term, say k, there are k occurrences of k in the sequence, and the distance between any two consecutive occurrences of k equals k.

1, 2, 3, 2, 5, 3, 7, 8, 3, 5, 11, 17, 13, 7, 5, 8, 28, 36, 4, 5, 7, 11, 4, 8, 5, 13, 4, 7, 17, 54, 4, 8, 11, 42, 7, 72, 56, 30, 13, 8, 70, 7, 40, 11, 28, 17, 60, 8, 7, 90, 140, 13, 84, 36, 11, 8, 150, 126, 80, 108, 105, 10, 17, 8, 13, 11, 120, 30, 280, 168

Offset

1,2

Comments

This sequence is a variant of A336215.

Will every integer appear in this sequence?

Links

Rémy Sigrist, Table of n, a(n) for n = 1..5000

Rémy Sigrist, C++ program for A336268

Example

For n = 1:
- we can choose a(1) = 1.
For n = 2:
- we can choose a(2) = 2,
- consequently: a(4) = 2.
- For n = 3:
- we can choose a(3) = 3,
- consequently: a(6) = a(9) = 3.
For n = 5:
- a(5) cannot be equal to 4 as a(9) = 3,
- we can choose a(5) = 5,
- consequently: a(10) = a(15) = a(20) = a(<25) = 5.

Prog

(C++) See Links section.

Crossrefs

Cf. A336215.

Sequence in context: A060474 A065988 A335285 * A075105 A265675 A094020

Adjacent sequences: A336265 A336266 A336267 * A336269 A336270 A336271

Keyword

nonn

Author

Rémy Sigrist, Jul 15 2020

Status

approved