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A349196
a(n) is the Y-coordinate of the n-th point of the R5 dragon curve; A349195 gives X-coordinates.
3
0, 0, 1, 1, 2, 2, 3, 3, 2, 2, 3, 3, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 4, 4, 5, 5, 4, 4, 3, 3, 2, 2, 3, 3, 2, 2, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, -1, -1, -2, -2, -1, -1, -2, -2, -1, -1, 0, 0, -1, -1, 0, 0, -1, -1, -2, -2, -3, -3, -2, -2, -3, -3
OFFSET
0,5
COMMENTS
The R5 dragon curve can be represented using an L-system.
FORMULA
a(5^k) = A006496(k) for any k >= 0.
EXAMPLE
The R5 dragon curve starts as follows:
+-----+
24| 25
|
|
+-----+ +-----+ +-----+
23 22| 11| 10| 7| 6|
| | | | |
21| 12| 9| 8| |
+-----+-----+-----+-----+-----+
20| 17| 16| 13| 4| 5
| | | | |
| | | | |
+-----+ +-----+ +-----+
19 18 15 14 3 2|
|
|
+-----+
0 1
- so a(0) = a(1) = 0,
a(2) = a(3) = a(14) = a(15) = a(18) = a(19) = 1.
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
sign
AUTHOR
Rémy Sigrist, Nov 10 2021
STATUS
approved