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A359216
X-coordinates of a point moving in a counterclockwise undulating spiral in a square grid.
4
0, 1, 1, 0, 0, -1, -1, -2, -2, -1, -1, 0, 0, 1, 1, 2, 2, 3, 3, 2, 2, 1, 1, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -5, -5, -4
OFFSET
0,8
COMMENTS
Y-coordinates are given in A359217.
The undulating spiral is
y ^
|
4 | 25--24
| | |
3 | 27--26 23--22
| | |
2 | 29--28 5---4 21--20
| | | | |
1 | 31--30 7---6 3---2 19--18
| | | | |
0 | 32--33 8---9 0---1 16--17
| | | | |
-1 | 34--35 10--11 14--15 46--47
| | | | |
-2 | 36--37 12--13 44--45
| | |
-3 | 38--39 42--43
| | |
-4 | 40--41
+------------------------------------>
-4 -3 -2 -1 0 1 2 3 4 x
FORMULA
a(2*n) = A329116(n). - Rémy Sigrist, Apr 01 2023
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
sign,walk
AUTHOR
Hans G. Oberlack, Dec 21 2022
STATUS
approved