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Primes of form: 2*n^2+2*n-41.
4

%I #7 Sep 08 2022 08:45:41

%S 19,43,71,103,139,179,223,271,379,439,503,571,643,719,883,971,1063,

%T 1259,1471,1583,1699,2203,2339,3079,3571,3919,4099,4283,4663,5059,

%U 5471,5683,6343,6571,6803,7039,7523,8539,8803,9343,9619,11059,11971,12919,13903

%N Primes of form: 2*n^2+2*n-41.

%H Vincenzo Librandi, <a href="/A155770/b155770.txt">Table of n, a(n) for n = 1..1000</a>

%e 19 is in this sequence because 2*5^2+2*5-41=19.

%t Select[Table[2 n^2 + 2 n - 41, {n, 4, 100}], PrimeQ] (* _Vincenzo Librandi_, Sep 11 2013 *)

%o (Magma) [a: n in [4..100] | IsPrime(a) where a is 2*n^2+2*n-41 ]; // _Vincenzo Librandi_, Sep 11 2013

%o (PARI) is(n)=isprime(2*n^2+2*n-41) \\ _Charles R Greathouse IV_, Sep 11 2013

%Y Cf. A155769, A155771, A155772.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Jan 27 2009