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Primes of the form 2*n^3-1.
2

%I #16 May 03 2024 19:55:49

%S 53,127,431,1999,8191,18521,27647,31249,59581,78607,159013,194671,

%T 314927,332749,390223,453961,524287,657017,1062881,1457999,1507141,

%U 1608713,1940597,2519423,3455999,4000751,4393999,5371237,5606441

%N Primes of the form 2*n^3-1.

%H Vincenzo Librandi, <a href="/A177105/b177105.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = 2*A214289(n)^3 -1. - _R. J. Mathar_, Aug 20 2019

%t Select[Table[2 n^3 - 1, {n, 0, 300}], PrimeQ] (* _Vincenzo Librandi_, Jul 25 2012 *)

%o (Magma) [a: n in [0..250] | IsPrime(a) where a is (2*n^3-1)];

%o (PARI) for(n=0, 200, if(isprime(k=2*n^3-1), print1(k", "))); \\ _Vincenzo Librandi_, Jul 25 2012

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_