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A054553
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Prime number spiral (clockwise, Northeast spoke).
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9
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2, 5, 41, 127, 269, 467, 751, 1093, 1523, 2027, 2621, 3299, 4007, 4861, 5749, 6763, 7867, 9041, 10273, 11719, 13121, 14723, 16319, 18061, 19963, 21851, 23857, 26021, 28289, 30661, 33029, 35531, 38201, 40993, 43759, 46751, 49789, 52957, 56197
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OFFSET
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0,1
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COMMENTS
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8-spoke wheel overlays prime number spiral; hub is 2 in shell 0; 8 spokes radiate from this hub; this is Northeast, clockwise.
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LINKS
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FORMULA
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EXAMPLE
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Begin a prime number spiral at shell 0 (prime 2), proceed clockwise, Northeast.
The spiral with four terms in every spoke looks like this:
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227 101--103--107--109--113--127
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223 97 29---31---37---41 131
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211 89 23 3----5 43 137
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199 83 19 2 7 47 139
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197 79 17---13---11 53 149
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193 73---71---67---61---59 151
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191--181--179--173--167--163--157
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(End)
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MATHEMATICA
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Table[ Prime[4n^2 - 10n + 7], {n, 1, 40} ]
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PROG
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(Magma) [NthPrime(4*n^2 - 10*n + 7): n in [1..40]]; // Vincenzo Librandi, Aug 29 2018
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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