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A173826
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Primes p such that p-+floor(Sqrt(p)) are primes.
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2
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5, 37, 47, 151, 331, 349, 593, 617, 907, 911, 937, 941, 1789, 1831, 2341, 2389, 2399, 2957, 3617, 3631, 3673, 3719, 4457, 5261, 5309, 6121, 6151, 6199, 6221, 7103, 7127, 7213, 8101, 8179, 9323, 9337, 9377, 10529, 10589, 11789, 13007, 13033, 13037
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OFFSET
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1,1
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COMMENTS
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5-+2->primes, 37-+6->primes,..
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LINKS
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MATHEMATICA
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f1[n_]:=n-Floor[Sqrt[n]]; f2[n_]:=n+Floor[Sqrt[n]]; lst={}; Do[p=Prime[n]; If[PrimeQ[f1[p]]&&PrimeQ[f2[p]], AppendTo[lst, p]], {n, 8!}]; lst
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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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