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A169647
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Primes p such that (p-2)/3 is not a prime number.
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4
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2, 3, 5, 7, 13, 19, 29, 31, 37, 43, 47, 61, 67, 73, 79, 83, 97, 101, 103, 107, 109, 127, 137, 139, 149, 151, 157, 163, 167, 173, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 241, 257, 263, 271, 277, 281, 283, 307, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379
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OFFSET
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1,1
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COMMENTS
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The old definition was "Start with the list of primes; accept 2 but remove the list of primes S(2), defined in the comments; accept the next prime (3) but remove the list of primes S(3); repeat".
If p is a prime, S(p) denotes the list of primes {3p+2, 3(3p+2)+2, 3(3(3p+2)+2)+2, ...}, stopping as soon as we reach the first composite number. Thus S(2) = {}, S(3) = {11}, S(5) = {17, 53}, S(7) = {23, 71}, etc.
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LINKS
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MATHEMATICA
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Select[Prime[Range[80]], !PrimeQ[(#-2)/3]&] (* Harvey P. Dale, Mar 08 2012 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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Checked by Dan Drake, Jun 17 2010
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STATUS
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approved
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