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%I #17 Mar 09 2023 11:28:03
%S 1,2,3,4,5,7,9,8,11,10,13,6,15,12,17,14,19,16,23,18,25,20,29,22,21,24,
%T 31,26,37,28,35,32,41,34,43,27,33,36,47,44,39,38,49,40,53,46,59,30,51,
%U 50,61,55,67,58,71,52,45,56,73,62,65,64,79,42,77,48,83
%N Counterclockwise spiral constructed of distinct terms such that any two terms a knight's move apart are coprime; always choose the smallest possible positive term.
%H Jodi Spitz, <a href="/A361299/b361299.txt">Table of n, a(n) for n = 1..4002</a>
%H Rémy Sigrist, <a href="/A361299/a361299.gp.txt">PARI program</a>
%e The spiral begins:
%e 33--27--43--34--41--32--35
%e | |
%e 36 19--14--17--12--15 28
%e | | | |
%e 47 16 5---4---3 6 37
%e | | | | | |
%e 44 23 7 1---2 13 26
%e | | | | |
%e 39 18 9---8--11--10 31
%e | | |
%e 38 25--20--29--22--21--24
%e |
%e 49--40--53--46---.---.---.
%o (PARI) See Links section.
%Y Cf. A308884.
%K nonn
%O 1,2
%A _Jodi Spitz_, Mar 08 2023
%E More terms from _Rémy Sigrist_, Mar 09 2023
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