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A128547
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Primes p such that p*q-p-q is prime where q=nextprime(p).
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5
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3, 5, 7, 13, 29, 37, 43, 71, 89, 107, 151, 163, 191, 199, 211, 239, 241, 277, 331, 401, 479, 569, 607, 643, 683, 719, 751, 773, 811, 823, 881, 907, 911, 937, 953, 1087, 1091, 1109, 1117, 1201, 1249, 1289, 1321, 1399, 1439, 1459, 1471, 1597, 1619, 1621, 1657
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OFFSET
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1,1
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LINKS
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EXAMPLE
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3*5-3-5=7 prime, 5*7-5-7=23 prime etc.
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MATHEMATICA
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qnpQ[n_]:=Module[{q=NextPrime[n]}, PrimeQ[n*q-n-q]]; Select[Prime[Range[ 500]], qnpQ] (* Harvey P. Dale, Feb 28 2015 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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