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A062403
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Primes of the form 2*k*prime(k) + 1.
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1
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5, 13, 31, 157, 239, 683, 1697, 3067, 4273, 5563, 6323, 6781, 9043, 13841, 16427, 22247, 22901, 23767, 27109, 32687, 33721, 45833, 58217, 61933, 83341, 90583, 94811, 115979, 158161, 172751, 193619, 202877, 221567, 284233, 297967, 308773
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OFFSET
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1,1
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LINKS
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MAPLE
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select(isprime, [seq(2*i*ithprime(i)+1, i=1..200)]); # Muniru A Asiru, Jun 29 2018
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PROG
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(PARI) je=[]; for(n=0, 200, if(isprime(2*n*prime(n)+1), je=concat(je, 2*n*prime(n)+1), )); je
(PARI) { n=c=0; forprime (p=2, 5*10^5, q=2*(c++)*p + 1; if (isprime(q), write("b062403.txt", n++, " ", q); if (n==1000, break)) ) } \\ Harry J. Smith, Aug 07 2009
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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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