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A102166 Numbers n such that 2*n^2 + 11*n + 101 is prime. 1

%I

%S 0,2,6,8,12,14,18,36,38,42,44,48,50,66,72,74,78,80,84,90,92,102,104,

%T 116,140,150,152,158,162,164,170,182,186,192,198,200,204,216,218,222,

%U 236,242,254,258,266,282,290,294,302,312,318,332,336,338,342,354,356,366

%N Numbers n such that 2*n^2 + 11*n + 101 is prime.

%C 2 is the smallest one digit prime, 11 is the smallest two digit prime and 101 is the smallest three digit prime.

%H Harvey P. Dale, <a href="/A102166/b102166.txt">Table of n, a(n) for n = 1..1000</a>

%e For n=0, 2*n^2 + 11*n + 101 = 2*0^2 + 11*0 + 101 = 101 (prime)

%e for n=48, 2*n^2 + 11*n + 101 = 2*48^2 + 11*48 + 101 = 5237 (prime)

%e for n=92, 2*n^2 + 11*n + 101 = 2*92^2 + 11*92 + 101 = 18041 (prime)

%t Select[Range[0,400],PrimeQ[2#^2+11#+101]&] (* _Harvey P. Dale_, Aug 16 2020 *)

%o (MAGMA) [n: n in [0..1000] | IsPrime(2*n^2 + 11*n + 101)] // _Vincenzo Librandi_, Nov 18 2010

%o (PARI) is(n)=isprime(2*n^2+11*n+101) \\ _Charles R Greathouse IV_, Jun 13 2017

%K nonn,easy

%O 1,2

%A _Parthasarathy Nambi_, Feb 15 2005

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Last modified December 4 02:40 EST 2021. Contains 349469 sequences. (Running on oeis4.)