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 A053705 Primes p of form q^k-2 where q is also a prime and k > 1. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 79=3^4-2, 243=3^5-2. LINKS MATHEMATICA 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 *) PROG (PARI) lista(nn) = forprime (p=1, nn, if (ispower(p+2, , &q) && isprime(q), print1(p, ", ")); ); \\ Michel Marcus, Dec 11 2014 CROSSREFS Cf. A025475. Subsequence of A053705. Sequence in context: A049572 A094786 A028871 * A247175 A049001 A049002 Adjacent sequences:  A053702 A053703 A053704 * A053706 A053707 A053708 KEYWORD nonn AUTHOR Labos Elemer, Feb 14 2000 EXTENSIONS Definition corrected by Zak Seidov, Dec 11 2014 STATUS approved

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Last modified August 3 21:19 EDT 2021. Contains 346441 sequences. (Running on oeis4.)