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Nonnegative numbers n such that 9*n^2 - 10*n + 3 is prime.
3

%I #18 Sep 08 2022 08:45:40

%S 0,1,2,4,8,14,22,26,28,34,38,44,46,50,52,68,70,82,86,88,100,112,118,

%T 122,124,140,146,148,152,158,170,182,188,190,196,212,224,232,236,248,

%U 256,278,280,284,286,290,292,298,310,314,334,356,374,376,380,388,394,400

%N Nonnegative numbers n such that 9*n^2 - 10*n + 3 is prime.

%C With the exception of the 1, all entries are == 2 (mod 6) or == 4 (mod 6), as in A047235, because otherwise 9*n^2-10*n+3 is divisible by 2 or 3. - _R. J. Mathar_, Jul 16 2012

%H Vincenzo Librandi, <a href="/A154264/b154264.txt">Table of n, a(n) for n = 1..1000</a>

%t lst={};Do[p=9*n^2-10*n+3;If[PrimeQ[p],AppendTo[lst,n]],{n,0,7!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Feb 21 2009 *)

%o (Magma) [n: n in [0..400] | IsPrime(9*n^2-10*n+3)]; // _Vincenzo Librandi_, Sep 24 2012

%o (PARI) is(n)=isprime(9*n^2-10*n+3) \\ _Charles R Greathouse IV_, May 22 2017

%Y Cf. A154261.

%K nonn,easy

%O 1,3

%A _Vincenzo Librandi_, Feb 21 2009

%E Edited by _Robert Hochberg_, Jun 21 2010