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%I #12 May 07 2017 12:32:03
%S 3,17,43,67,113,523,2017,2243,4817,8363,9283,16433,17713,19267,30817,
%T 56843,81667,97283,141067,149153,185153,203873,271363,279073,329473,
%U 398353,400417,455953,472643,481667,513923,519793,530443,549643,670673,684113,746243
%N Primes of the form (n^2+2)/6 where n^2+1 is prime.
%C The corresponding n are in A215248.
%H Harvey P. Dale, <a href="/A215429/b215429.txt">Table of n, a(n) for n = 1..1000</a>
%e 3 is in the sequence because, for n = 4, 4^2 + 1 = 17 and (4^2 + 2)/6 = 3 are primes.
%t lst={}; Do[ p=n^2+ 1; q=(p+1)/6;If[PrimeQ[p]&&PrimeQ[q], AppendTo[lst, q]], {n, 0, 2500}]; lst
%t Select[(#+1)/6&/@Select[Range[3000]^2+1,PrimeQ],PrimeQ] (* _Harvey P. Dale_, May 07 2017 *)
%Y Cf. A005574, A002496, A215248.
%K nonn
%O 1,1
%A _Michel Lagneau_, Aug 10 2012
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