%I #13 Apr 22 2023 00:00:17
%S 20,5,12,9,14,11,8,16,7,19,3,17,2,15,10,6,13,4,18,1,20,5,12,9,14,11,8,
%T 16,7,19,3,17,2,15,10,6,13,4,18,1,20,5,12,9,14,11,8,16,7,19,3,17,2,15,
%U 10,6,13,4,18,1,20,5,12,9,14,11
%N Numbers on a standard, London, or clock dartboard read in a counterclockwise direction.
%C Sequence is periodic with period 20. - _Michel Marcus_, Jul 26 2013
%D GCHQ, The GCHQ Puzzle Book, Penguin, 2016. See page 82.
%H K. S. Brown, <a href="http://www.mathpages.com/home/kmath025.htm">The Dartboard Sequence</a>
%H Patrick Chaplin, <a href="http://web.ukonline.co.uk/patrick.chaplin/Darts_History/why_are_the_numbers_on_a_dartboa.htm">Why are the numbers on a dartboard in the order they are?</a>
%H Sven Silow, <a href="http://www.thedartmart.com/dart_faq/Sect1/14.htm">Why this particular numbering scheme?</a>
%H <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).
%Y Cf. A003833, A008575.
%K nonn
%O 0,1
%A Andrew G. West (WestA(AT)wlu.edu), Mar 09 2005