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A153143
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Numbers n such that 2n+19 is prime.
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5
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0, 2, 5, 6, 9, 11, 12, 14, 17, 20, 21, 24, 26, 27, 30, 32, 35, 39, 41, 42, 44, 45, 47, 54, 56, 59, 60, 65, 66, 69, 72, 74, 77, 80, 81, 86, 87, 89, 90, 96, 102, 104, 105, 107, 110, 111, 116, 119, 122, 125, 126, 129, 131, 132, 137, 144, 146, 147, 149, 156, 159, 164, 165
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Or, (p-19)/2 for primes p >= 19.
a(n) = (A000040(n+7)-19)/2.
a(n) = A005097(n+6)-9.
a(n) = A067076(n+6)-8.
a(n) = A089038(n+5)-7.
a(n) = A105760(n+4)-6.
a(n) = A101448(n+3)-4.
a(n) = A089559(n+1)-2.
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EXAMPLE
| For n = 4, 2*n+19 = 27 is not prime, so 4 is not in the sequence; for n = 17, 2*n+19 = 53 is prime, so 17 is in the sequence.
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MATHEMATICA
| (Prime[Range[8, 100]]-19)/2 [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Feb 08 2010]
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PROG
| (MAGMA) [ n: n in [0..165] | IsPrime(2*n+19) ];
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CROSSREFS
| Cf. A000040 (prime numbers), A005097 (2n+1 is prime), A067076 (2n+3 is prime), A089038 (2n+5 is prime), A105760 (2n+7 is prime), A101448 (2n+11 is prime), A089559 (2n+15 is prime), A153144 (2n+19 is not prime).
Sequence in context: A122701 A032925 A166087 * A075724 A049408 A138970
Adjacent sequences: A153140 A153141 A153142 * A153144 A153145 A153146
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KEYWORD
| nonn
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 19 20
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EXTENSIONS
| Edited, corrected and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Dec 22 2008
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