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Primes of the form 81n^2 - 90n + 26.
4

%I #19 Sep 08 2022 08:45:38

%S 17,1601,8837,16901,33857,65537,160001,190097,240101,295937,401957,

%T 577601,1136357,1336337,1378277,1464101,1552517,1833317,2464901,

%U 2755601,3519377,3587237,3865157,4227137,4301477,5410277,5664401,6100901

%N Primes of the form 81n^2 - 90n + 26.

%H Vincenzo Librandi, <a href="/A144571/b144571.txt">Table of n, a(n) for n = 1..2000</a>

%t lst={};Do[If[PrimeQ[p=81*n^2-90*n+26],AppendTo[lst,p]],{n,7!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Jan 11 2009 *)

%t Select[Table[81 n^2 - 90 n + 26, {n, 300}], PrimeQ] (* _Vincenzo Librandi_, Jan 02 2014 *)

%o (Magma) [a: n in [0..300] | IsPrime(a) where a is 81*n^2-90*n+26 ]; // _Vincenzo Librandi_, Jan 02 2014

%Y Cf. A154295.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Jan 06 2009

%E a(1) corrected by _Jon E. Schoenfield_, Jun 17 2010