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A091177
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Numbers m such that the m-th prime is of the form 3*k-1.
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11
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1, 3, 5, 7, 9, 10, 13, 15, 16, 17, 20, 23, 24, 26, 28, 30, 32, 33, 35, 39, 40, 41, 43, 45, 49, 51, 52, 54, 55, 56, 57, 60, 62, 64, 66, 69, 71, 72, 76, 77, 79, 81, 83, 86, 87, 89, 91, 92, 94, 96, 97, 98, 102, 103, 104, 107, 108, 109, 113, 116, 118, 119, 120, 123
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OFFSET
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1,2
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COMMENTS
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The asymptotic density of this sequence is 1/2 (by Dirichlet's theorem). - Amiram Eldar, Feb 28 2021
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LINKS
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FORMULA
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MATHEMATICA
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PrimePi/@Select[3Range[0, 250]-1, PrimeQ] (* Harvey P. Dale, Apr 26 2011 *)
Select[Range[150], IntegerQ[(Prime[#]+1)/3]&] (* Harvey P. Dale, Dec 14 2021 *)
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PROG
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(PARI) a091177(limit)={my(m=0); forprime(p=2, prime(limit), m++; if(p%3==2, print1(m, ", ")))};
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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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STATUS
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approved
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