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%I #33 Feb 20 2022 04:19:26
%S 2,3,31,107,241,443,709,1049,1471,1973,2539,3191,3911,4729,5651,6637,
%T 7699,8867,10133,11503,12941,14537,16073,17863,19727,21601,23609,
%U 25759,27967,30319,32719,35201,37831,40627,43391,46399,49411,52553,55813
%N Prime number spiral (clockwise, North spoke).
%C Smallest prime in n-th shell of prime spiral.
%C 8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is North, clockwise.
%C Shell 1 comprises the primes 3 5 7 11 13 17 19 23; 3 is lowest, 23 is highest.
%C The wheel may be rotated, but the sequences though pointing in different directions, will remain the same.
%H Ivan Panchenko, <a href="/A054551/b054551.txt">Table of n, a(n) for n = 0..1000</a>
%H Hermetic Systems, <a href="http://www.hermetic.ch/pns/pns.htm">Prime Number Spiral</a>.
%F a(n) = A000040(A054552(n)). - _R. J. Mathar_, Aug 29 2018
%e Begin a prime number spiral at zero, proceed clockwise, North.
%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 - 3n + 1], {n, 0, 40} ]
%Y Cf. A000040, A054552, A054553, A054555, A054564, A054566, A054568, A054570, A053999.
%K easy,nonn
%O 0,1
%A _Enoch Haga_ and _G. L. Honaker, Jr._ Apr 09 2000
%E Edited by _Robert G. Wilson v_, Feb 25 2002
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