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A053705
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Primes p of form q^k-2 where q is also a prime and k > 1.
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3
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2, 7, 23, 47, 79, 167, 241, 359, 727, 839, 1367, 1847, 2207, 2399, 3719, 5039, 6857, 7919, 10607, 11447, 14639, 16127, 17159, 19319, 19681, 28559, 29789, 29927, 36479, 44519, 49727, 50651, 54287, 57119, 66047, 85847, 97967, 113567, 128879
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OFFSET
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1,1
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COMMENTS
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79=3^4-2, 243=3^5-2.
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LINKS
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MATHEMATICA
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Do[s=2+Prime[n]; If[Equal[Length[FactorInteger[s]], 1]&&!PrimeQ[s], Print[s-2]], {n, 1, 100000}]
fQ[n_] := PrimeNu[n + 2] == 1 && ! PrimeQ[n + 2]; Select[ Prime@ Range@ 15000, fQ] (* Robert G. Wilson v, Apr 01 2012 *)
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PROG
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(PARI) lista(nn) = forprime (p=1, nn, if (ispower(p+2, , &q) && isprime(q), print1(p, ", ")); ); \\ Michel Marcus, Dec 11 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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