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A124670
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(Product of successive primes minus 2) divided by 3 is prime.
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1
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11, 47, 73, 107, 587, 673, 3467, 3673, 4783, 7499, 10799, 17327, 29983, 33073, 62207, 71147, 72073, 137387, 225227, 243673, 252283, 355007, 442367, 504299, 554699, 567673, 735073, 874799, 924073, 961067, 1062073, 1175627, 1326673, 1486847
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OFFSET
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1,1
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LINKS
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Harvey P. Dale, Table of n, a(n) for n = 1..1000
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EXAMPLE
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11*13 = 143, 143-2 = 141, 141/3 = 47 is the second entry.
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MATHEMATICA
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Select[(Times@@@Partition[Prime[Range[500]], 2, 1]-2)/3, PrimeQ] (* Harvey P. Dale, Oct 02 2012 *)
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PROG
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(PARI) g(n) = { for(x=1, n, y=prime(x)*prime(x+1)-2; if(y%3==0, if(isprime(y/3), print1(y/3", ")))) }
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CROSSREFS
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Cf. A123921.
Sequence in context: A238665 A044113 A044494 * A142103 A031910 A009941
Adjacent sequences: A124667 A124668 A124669 * A124671 A124672 A124673
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KEYWORD
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easy,nonn
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AUTHOR
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Cino Hilliard, Dec 27 2006
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STATUS
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approved
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