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Search: id:A153145
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| A153145 |
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Numbers n such that n and 2n+19 are both prime. |
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+0
1
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| 2, 5, 11, 17, 41, 47, 59, 89, 107, 131, 137, 149, 167, 191, 251, 269, 311, 317, 389, 401, 419, 431, 461, 467, 479, 521, 587, 599, 641, 677, 797, 809, 839, 857, 929, 941, 947, 977, 1031, 1061, 1097, 1109, 1181, 1187, 1229, 1301, 1307, 1319, 1361, 1367, 1409
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Or, primes p such that 2p+19 is also prime.
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EXAMPLE
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For n=2, 2*n+19 = 23 is prime, so 2 is in the sequence; for n=17, 2*n+19 = 53 is prime, so 17 is in the sequence.
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PROGRAM
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(MAGMA) [ p: p in PrimesUpTo(1500) | IsPrime(2*p+19) ];
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CROSSREFS
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Cf. A153143 (2n+19 is prime), A005384 (Sophie Germain primes, n and 2n+1 are both prime), A023204 (n and 2n+3 are both prime), A023205 (n and 2n+5 are both prime), A023206 (n and 2n+7 are both prime), A023207 (n and 2n+9 are both prime).
Sequence in context: A133928 A126204 A091936 this_sequence A144572 A038977 A141778
Adjacent sequences: A153142 A153143 A153144 this_sequence A153146 A153147 A153148
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KEYWORD
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nonn
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AUTHOR
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Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Dec 19 20
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EXTENSIONS
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Edited, corrected and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Dec 22 2008
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