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Prime number spiral (clockwise, Southwest spoke).
8

%I #18 Feb 19 2022 13:11:09

%S 2,17,73,191,367,607,919,1297,1753,2309,2909,3623,4421,5303,6257,7307,

%T 8447,9643,10979,12421,13883,15467,17203,19037,20921,22853,24953,

%U 27091,29389,31859,34267,36847,39551,42307,45233,48311,51407,54547,57781

%N Prime number spiral (clockwise, Southwest spoke).

%H Ivan Panchenko, <a href="/A054568/b054568.txt">Table of n, a(n) for n = 0..1000</a>

%F 8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is Southwest, clockwise.

%F a(n) = A000040(A054569(n+1)). - _R. J. Mathar_, Aug 29 2018

%e Begin a prime number spiral at shell 0 (prime 2), proceed clockwise, Southwest.

%e From _Omar E. Pol_, Feb 19 2022: (Start)

%e The spiral with four terms in every spoke looks like this:

%e .

%e 227 101--103--107--109--113--127

%e | | |

%e 223 97 29---31---37---41 131

%e | | | | |

%e 211 89 23 3----5 43 137

%e | | | | | | |

%e 199 83 19 2 7 47 139

%e | | | | | |

%e 197 79 17---13---11 53 149

%e | | | |

%e 193 73---71---67---61---59 151

%e | |

%e 191--181--179--173--167--163--157

%e .

%e (End)

%t Table[ Prime[4n^2 - 6n + 3], {n, 1, 40} ]

%Y Cf. A054569, A054551, A054553, A054555, A054564, A054566, A054570, A053999.

%K easy,nonn

%O 0,1

%A _Enoch Haga_ and _G. L. Honaker, Jr._, Apr 10 2000

%E Edited by _Robert G. Wilson v_, Feb 25 2002