OFFSET
0,3
COMMENTS
This sequence is a permutation of the nonnegative integers with inverse A334672:
- we can always extend the sequence with a power of 4,
- eventually every power of 4 appears in the sequence,
- a power of 4 is followed by the least value not yet in the sequence,
- so eventually every integer will appear.
LINKS
EXAMPLE
The first terms, alongside a(n) AND a(n+1), are:
n a(n) a(n) AND a(n+1)
-- ---- ---------------
0 0 0^2
1 1 0^2
2 2 0^2
3 4 0^2
4 3 1^2
5 5 2^2
6 6 0^2
7 8 0^2
8 7 1^2
9 9 3^2
10 11 3^2
11 13 0^2
12 16 0^2
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Oct 31 2020
STATUS
approved