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A054570
Prime number spiral (clockwise, West spoke).
8
2, 19, 83, 199, 389, 641, 967, 1361, 1823, 2377, 3001, 3709, 4517, 5419, 6353, 7477, 8623, 9791, 11159, 12577, 14083, 15667, 17417, 19273, 21149, 23063, 25229, 27431, 29683, 32183, 34543, 37171, 39877, 42641, 45599, 48673, 51719, 54973, 58171
OFFSET
0,1
LINKS
FORMULA
8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is West, clockwise.
a(n) = A000040(A033951(n)). - R. J. Mathar, Aug 29 2018
EXAMPLE
Begin a prime number spiral at shell 0 (prime 2), proceed clockwise, West.
From Omar E. Pol, Feb 19 2022: (Start)
The spiral with four terms in every spoke looks like this:
.
227 101--103--107--109--113--127
| | |
223 97 29---31---37---41 131
| | | | |
211 89 23 3----5 43 137
| | | | | | |
199 83 19 2 7 47 139
| | | | | |
197 79 17---13---11 53 149
| | | |
193 73---71---67---61---59 151
| |
191--181--179--173--167--163--157
.
(End)
MATHEMATICA
Table[ Prime[4n^2 + 3n + 1], {n, 0, 40} ]
KEYWORD
easy,nonn
AUTHOR
EXTENSIONS
Edited by Frank Ellermann, Feb 24 2002
STATUS
approved