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%I A247845 #29 Sep 08 2022 08:46:09
%S A247845 5,62417,178817,261017,419147,433787,505607,876107,1183337,1374377,
%T A247845 1620917,1976987,3619607,4146377,5260487,5622047,6399677,7166147,
%U A247845 7213847,7743647,8055167,10615967,13277717,14042117,14080277,15331397,17433407,17889587,17963867
%N A247845 Primes, p, that generate the prime quadruplets, p^2-2p+2k (for k = -2, -1, 1, 2).
%C A247845 Except for a(1), all other terms in the sequence end in 7.
%C A247845 For a similar list not restricted to primes, see A247882.
%e A247845 5 is in the sequence as it generates the prime quadruplet 5^2-2*5-4=11; 5^2-2*5-2=13; 5^2-2*5+2=17; and, 5^2-2*5+4=19.
%o A247845 (PARI) lista(nn) = {vk = [-2, -1, 1, 2]; forprime (p=2, nn, nb = 0; for (k=1, 4, nb += isprime(p^2-2*p+2*vk[k]);); if (nb == 4, print1(p, ", ")););} \\ _Michel Marcus_, Sep 26 2014
%o A247845 (Magma) [p: p in PrimesUpTo(10^7) |IsPrime(p^2-2*p-4) and IsPrime(p^2-2*p-2)and IsPrime(p^2-2*p+2)and IsPrime(p^2-2*p+4)]; // _Vincenzo Librandi_, Oct 14 2014
%Y A247845 Cf. A247846 (lesser of prime quadruplets), A247882 (similar but not restricted to primes).
%K A247845 nonn
%O A247845 1,1
%A A247845 _Ray G. Opao_, Sep 25 2014
%E A247845 More terms from _Michel Marcus_, Oct 10 2014

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