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A054551 Prime number spiral (clockwise, North spoke).

%I A054551 #33 Feb 20 2022 04:19:26
%S A054551 2,3,31,107,241,443,709,1049,1471,1973,2539,3191,3911,4729,5651,6637,
%T A054551 7699,8867,10133,11503,12941,14537,16073,17863,19727,21601,23609,
%U A054551 25759,27967,30319,32719,35201,37831,40627,43391,46399,49411,52553,55813
%N A054551 Prime number spiral (clockwise, North spoke).
%C A054551 Smallest prime in n-th shell of prime spiral.
%C A054551 8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is North, clockwise.
%C A054551 Shell 1 comprises the primes 3 5 7 11 13 17 19 23; 3 is lowest, 23 is highest.
%C A054551 The wheel may be rotated, but the sequences though pointing in different directions, will remain the same.
%H A054551 Ivan Panchenko, <a href="/A054551/b054551.txt">Table of n, a(n) for n = 0..1000</a>
%H A054551 Hermetic Systems, <a href="http://www.hermetic.ch/pns/pns.htm">Prime Number Spiral</a>.
%F A054551 a(n) = A000040(A054552(n)). - _R. J. Mathar_, Aug 29 2018
%e A054551 Begin a prime number spiral at zero, proceed clockwise, North.
%e A054551 From _Omar E. Pol_, Feb 19 2022: (Start)
%e A054551 The spiral with four terms in every spoke looks like this:
%e A054551 .
%e A054551   227  101--103--107--109--113--127
%e A054551    |     |                       |
%e A054551   223   97   29---31---37---41  131
%e A054551    |     |    |              |   |
%e A054551   211   89   23    3----5   43  137
%e A054551    |     |    |    |    |    |   |
%e A054551   199   83   19    2    7   47  139
%e A054551    |     |    |         |    |   |
%e A054551   197   79   17---13---11   53  149
%e A054551    |     |                   |   |
%e A054551   193   73---71---67---61---59  151
%e A054551    |                             |
%e A054551   191--181--179--173--167--163--157
%e A054551 .
%e A054551 (End)
%t A054551 Table[ Prime[4n^2 - 3n + 1], {n, 0, 40} ]
%Y A054551 Cf. A000040, A054552, A054553, A054555, A054564, A054566, A054568, A054570, A053999.
%K A054551 easy,nonn
%O A054551 0,1
%A A054551 _Enoch Haga_ and _G. L. Honaker, Jr._ Apr 09 2000
%E A054551 Edited by _Robert G. Wilson v_, Feb 25 2002