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A349218
a(n) is the X-coordinate of the n-th point of the 7-dragon curve; sequence A349219 gives Y-coordinates.
2
0, 1, 0, 1, 1, 2, 1, 2, 1, 1, 0, 1, 0, 0, -1, 0, -1, 0, 0, 1, 0, 1, 1, 2, 2, 1, 1, 2, 2, 3, 2, 3, 3, 4, 3, 4, 3, 3, 2, 3, 2, 2, 1, 2, 1, 2, 2, 3, 2, 3, 2, 2, 1, 2, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, -1, 0, -1, -1, -2, -1, -2, -1, -1, 0, -1, 0, -1, -1, -2, -1
OFFSET
0,6
COMMENTS
Coordinates are given on a hexagonal lattice with X-axis and Y-axis as follows (the Y-axis corresponds to the sixth primitive root of unity):
Y
/
/
0 ---- X
The 7-dragon curve can be represented using an L-system.
EXAMPLE
The 7-dragon curve starts as follows:
14 12
\ / \
\ / \
10,13--8,11
\ / \
\ / \
2---3,6,9---7
\ / \
\ / \
0----1,4----5
- so a(0) = a(2) = a(10) = a(12) = a(13) = 0,
a(1) = a(3) = a(4) = a(6) = a(8) = a(9) = a(11) = 1,
a(5) = a(7) = 2,
a(14) = -1.
PROG
(PARI) See Links section.
CROSSREFS
See A349040 and A349197 for similar sequences.
Cf. A349219.
Sequence in context: A342627 A220115 A039924 * A364205 A275346 A037888
KEYWORD
sign
AUTHOR
Rémy Sigrist, Nov 11 2021
STATUS
approved