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A361299 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.

%I A361299 #17 Mar 09 2023 11:28:03
%S A361299 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 A361299 31,26,37,28,35,32,41,34,43,27,33,36,47,44,39,38,49,40,53,46,59,30,51,
%U A361299 50,61,55,67,58,71,52,45,56,73,62,65,64,79,42,77,48,83
%N A361299 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 A361299 Jodi Spitz, <a href="/A361299/b361299.txt">Table of n, a(n) for n = 1..4002</a>
%H A361299 Rémy Sigrist, <a href="/A361299/a361299.gp.txt">PARI program</a>
%e A361299 The spiral begins:
%e A361299   33--27--43--34--41--32--35
%e A361299    |                       |
%e A361299   36  19--14--17--12--15  28
%e A361299    |   |               |   |
%e A361299   47  16   5---4---3   6  37
%e A361299    |   |   |       |   |   |
%e A361299   44  23   7   1---2  13  26
%e A361299    |   |   |           |   |
%e A361299   39  18   9---8--11--10  31
%e A361299    |   |                   |
%e A361299   38  25--20--29--22--21--24
%e A361299    |
%e A361299   49--40--53--46---.---.---.
%o A361299 (PARI) See Links section.
%Y A361299 Cf. A308884.
%K A361299 nonn
%O A361299 1,2
%A A361299 _Jodi Spitz_, Mar 08 2023
%E A361299 More terms from _Rémy Sigrist_, Mar 09 2023