OFFSET

1,2

COMMENTS

This sequence is a permutation of the natural numbers (with inverse A319024):

- this sequence is injective,

- this sequence is surjective: by contradiction:

- let m be the least integer missing from the sequence,

- as a(1) = 1, we have m > 1,

- however the only positive integer belonging to both sequences is 1,

- hence a contradiction, QED.

LINKS

EXAMPLE

n a(n) b(n) t(n)

-- ---- ---- ----

1 1 2 3

2 2 4 4

3 3 5 9

4 4 8 6

5 5 6 7

6 9 10 27

7 8 16 14

8 6 9 10

9 7 11 11

10 10 12 12

11 27 29 81

12 16 32 20

13 14 19 16

14 11 13 13

15 12 17 18

16 29 30 31

17 81 82 243

18 32 64 34

19 20 24 22

20 19 21 21

PROG

(PARI) See Links section.

CROSSREFS

KEYWORD

AUTHOR

Rémy Sigrist, Sep 08 2018

STATUS

approved