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%I #12 Nov 26 2017 13:59:20
%S 3,6,11,18,21,23,27,32,42,48,51,83,86,93,116,153,158,182,188,216,282,
%T 291,317,333,396,482,681,737,786,798,818,821,872,923,956,966,977,986,
%U 1007,1026,1077,1082,1106,1161,1287,1292,1302,1337,1341,1451,1467,1563
%N Numbers n such that n^2 + n + 5 and n^2 + n - 5 are both prime.
%H Robert Israel, <a href="/A161864/b161864.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=3 as 12+-5 are primes. a(2)=6 as 42+-5 are primes.
%p select(n -> isprime(n^2+n+5) and isprime(n^2+n-5), [$1..2000]); # _Robert Israel_, Nov 26 2017
%t q=5;lst5={};Do[p=n^2+n;If[PrimeQ[p-q]&&PrimeQ[p+q],AppendTo[lst5,n]], {n,0,7!}];lst5
%Y Cf. A088485, A161863.
%K nonn,easy
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jun 20 2009
%E Definition rephrased by _R. J. Mathar_, Jun 23 2009