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%I #14 Sep 08 2022 08:46:02
%S 17569,43781,70321,229561,251231,426131,426551,453289,635051,727201,
%T 729791,741709,944689,981091,1015309,1078081,1128761,1228429,1231229,
%U 1282961,1289149,1302349,1351099,1723481,1763159,1823779,2078339,2260889,2336519,2357879
%N Primes p such that 2p^2-1, 3p^2-2, 4p^2-3, and 5p^2-4 are also prime.
%C Subsequence of A213079: a(1) = 17569 = A213079(10) =A213078(44)= A106483(389) = A000040(2019).
%H Vincenzo Librandi, <a href="/A213107/b213107.txt">Table of n, a(n) for n = 1..740</a>
%t Select[Prime[Range[200000]], PrimeQ[2 #^2 - 1] && PrimeQ[3 #^2 - 2] && PrimeQ[4 #^2 - 3] && PrimeQ[5 #^2 - 4] &] (* _T. D. Noe_, Jun 06 2012 *)
%o (Magma) [p: p in PrimesUpTo(2500000) | forall{i*p^2-i+1: i in [2..5] | IsPrime(i*p^2-i+1)}]; // _Vincenzo Librandi_, Apr 08 2013
%Y Cf. A000040, A106483, A213078, A213079.
%K nonn,easy
%O 1,1
%A _Zak Seidov_, Jun 05 2012
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