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A244512
The angle of the center of each numbered sector of a standard competition dartboard.
2
288, 54, 90, 324, 252, 0, 126, 162, 216, 18, 180, 234, 342, 198, 36, 144, 72, 306, 108, 270
OFFSET
1,1
COMMENTS
A standard dartboard is divided into 20 sectors each subtending an angle of 18 degrees.
The sequence is generated by considering the positive x-axis to be running through the center of the sector numbered "6" and defining this to be 0 degrees. The angular position of each sector is then defined relative to this position through a clockwise rotation of a line collinear with x until the line divides the sector of interest. The numbers are then sectors are ordered from 1 to 20 generating the full sequence.
It is a mere formality to fully define the bounds of each sector by adding and subtracting 9 degrees from each of the numbers in the sequence.
FORMULA
n = A003833(a(n)/18+6). - Jens Kruse Andersen, Jul 19 2014
CROSSREFS
Sequence in context: A011817 A334008 A035882 * A214301 A296902 A371948
KEYWORD
nonn,fini,full
AUTHOR
Philip Mizzi, Jun 29 2014
EXTENSIONS
Incorrect term removed by Jens Kruse Andersen, Jul 19 2014
STATUS
approved