OFFSET
0,4
COMMENTS
We only consider cells turned ON at stage n (and that were OFF in prior stages).
LINKS
EXAMPLE
The first 5 generations can be depicted as follows:
+-------+ +-------+
| 5 | | 5 |
| +---+-------------------+---+ |
| | 4 | |
+---+ +-------+---+-------+ +---+
| | 3 | | 3 | |
| | +---+---+---+ | |
| | | 2 | | |
| +---+ +---+ +---+ |
| | | | 1 | | | |
| +---+ +---+ +---+ |
| | 3 | | | |
| | +---+---+---+ | |
| | | | 3 | |
+---+ +-------+---+-------+ +---+
| 5 | | |
| +---+-------------------+---+ |
| | | 5 |
+-------+ +-------+
- so a(0) = 0,
a(1) = 1,
a(2) = 1,
a(3) = 4,
a(4) = 1,
a(5) = 4.
PROG
(C++) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Jan 09 2022
STATUS
approved