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A163080
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Primes p such that p$ - 1 is also prime. Here '$' denotes the swinging factorial function (A056040).
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3
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3, 5, 7, 13, 41, 47, 83, 137, 151, 229, 317, 389, 1063
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| a(n) are the primes in A163078.
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REFERENCES
| Peter Luschny, "Divide, swing and conquer the factorial and the lcm{1,2,...,n}", preprint, April 2008.
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LINKS
| Peter Luschny, Swinging Primes.
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EXAMPLE
| 3 is prime and 3$ - 1 = 5 is prime, so 3 is in the sequence.
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MAPLE
| a := proc(n) select(isprime, select(k -> isprime(A056040(k)-1), [$0..n])) end:
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CROSSREFS
| Cf. A163079, A163078, A103317.
Sequence in context: A047933 A075557 A057187 * A141414 A064268 A118743
Adjacent sequences: A163077 A163078 A163079 * A163081 A163082 A163083
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KEYWORD
| nonn
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AUTHOR
| Peter Luschny (peter(AT)luschny.de), Jul 21 2009
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