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%I #20 Sep 08 2022 08:45:40
%S 1,2,4,5,7,12,13,20,23,25,27,28,32,33,34,35,39,42,44,47,48,49,50,54,
%T 57,75,79,82,88,89,92,95,98,99,100,103,109,110,114,117,119,120,123,
%U 132,134,137,139,147,148,160,169,172,180,189,190,193,194,200,202,203,204,205
%N Numbers k such that k^3 + 2*k^2 + k + 1 is prime.
%C One less than the entry in A111501. - _R. J. Mathar_, Jan 05 2011
%H Vincenzo Librandi, <a href="/A154686/b154686.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[0, 100], PrimeQ[#^3 + 2 #^2 + # + 1]&] (* _Vincenzo Librandi_, Sep 24 2012 *)
%o (Magma) [n: n in [0..210] | IsPrime(n^3+2*n^2+n+1)]; // _Vincenzo Librandi_, Sep 24 2012
%o (PARI) is(n)=isprime(n^3+2*n^2+n+1) \\ _Charles R Greathouse IV_, May 22 2017
%Y Cf. A111501, A162292 (associated primes).
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Jan 19 2009
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