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A096177
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Primes p such that primorial(p)/2+2 is prime.
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7
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2, 3, 5, 7, 13, 29, 31, 37, 47, 59, 109, 223, 307, 389, 457, 1117, 1151, 2273, 9137, 10753, 15727, 25219, 26459, 29251, 30259
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Discussion group for the primality-testing program PrimeForm.
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EXAMPLE
| a(3)=7 because primorial(7)/2+2=A070826(4)+2=2*3*5*7/2+2=107 is prime.
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MATHEMATICA
| k = 1; Do[If[PrimeQ[n], k = k*n; If[PrimeQ[k/2 + 2], Print[n]]], {n, 2, 100000}] (Propper)
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PROG
| (PARI) P=1/2; forprime(p=2, 1e4, if(isprime((P*=p)+2), print1(p", "))) \\ Charles R Greathouse IV, Mar 14, 2011
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CROSSREFS
| Cf. A070826, A096178 primes of the form primorial(p)/2+2, A096547 primes p such that primorial(p)/2-2 is prime, A067024 smallest p+2 that has n distinct prime factors, A014545 primorial primes, A087398.
Sequence in context: A103597 A037021 A114741 * A075238 A158281 A115261
Adjacent sequences: A096174 A096175 A096176 * A096178 A096179 A096180
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KEYWORD
| more,nonn
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AUTHOR
| Hugo Pfoertner (hugo(AT)pfoertner.org), Jun 27 2004
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EXTENSIONS
| 7 additional terms, corresponding to probable primes, from Ryan Propper (rpropper(AT)stanford.edu), Jul 03 2005
Edited by T. D. Noe (noe(AT)sspectra.com), Oct 30 2008
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