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A096547
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Primes p such that primorial(p)/2-2 is prime.
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5
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5, 7, 11, 13, 17, 19, 23, 31, 41, 53, 71, 103, 167, 431, 563, 673, 727, 829, 1801, 2699, 4481, 6121, 7283, 9413, 10321, 12491, 17807, 30307
(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=103 is prime.
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MATHEMATICA
| k = 1; Do[k *= Prime[n]; If[PrimeQ[k - 2], Print[Prime[n]]], {n, 2, 3276}] (Propper)
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CROSSREFS
| Cf. A070826, A096177 primes p such that primorial(p)/2+2 is prime, A096178 primes of the form primorial(p)/2+2, A014545 primorial primes, A087398.
Sequence in context: A020589 A101635 A118941 * A128824 A098420 A093495
Adjacent sequences: A096544 A096545 A096546 * A096548 A096549 A096550
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KEYWORD
| nonn
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AUTHOR
| Hugo Pfoertner (hugo(AT)pfoertner.org), Jun 27 2004
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EXTENSIONS
| 5 more terms from Ryan Propper (rpropper(AT)stanford.edu), Oct 25 2005
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