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A237423
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Primes p such that prime(prime(p^2)) - 2 is also prime.
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1
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13, 17, 167, 179, 211, 223, 337, 373, 541, 661, 743, 751, 1063, 1129, 1217, 1607, 1697, 1741, 1913, 2017, 2039, 2083, 2293, 2389, 2447, 2459, 2543, 2677, 2693, 2711, 2851, 2909, 3083, 3191, 3209, 3259, 3571, 3889, 3917
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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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13 is prime and appears in the sequence because prime(prime(13^2)) - 2 = 8009 which is also prime.
17 is prime and appears in the sequence because prime(prime(17^2)) - 2 = 16139 which is also prime.
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MAPLE
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KD := proc() local a, b; a:=ithprime(n); b:=ithprime(ithprime(a^2))-2; if isprime (b) then RETURN (a); fi; end: seq(KD(), n=1..500);
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MATHEMATICA
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p[n_] := PrimeQ[Prime[Prime[n^2]] - 2]; n = 0; Do[If[p[Prime[m]], n = n + 1; Print[n, " ", Prime[m]]], {m, 1000}] (* Bajpai *)
Select[Prime[Range[105]], PrimeQ[Prime[Prime[#^2]] - 2] &] (* Wouter Meeussen, Feb 09 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base,less
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AUTHOR
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STATUS
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approved
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