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Primes of the form k^2+3*k+223.
1

%I #10 Oct 05 2024 09:39:24

%S 223,227,233,241,251,263,277,293,311,331,353,431,461,563,601,641,683,

%T 727,773,821,977,1033,1091,1151,1213,1277,1481,1553,1627,1861,2027,

%U 2113,2383,2477,2671,3083,3191,3301,3413,3527,3643,3761,3881,4003,4127,4253

%N Primes of the form k^2+3*k+223.

%H Vincenzo Librandi, <a href="/A153424/b153424.txt">Table of n, a(n) for n = 1..1000</a>

%t Table[n^2+3*n+223,{n,0,70}],PrimeQ] (* _Vincenzo Librandi_, Jul 14 2012 *)

%o (Magma) [a: n in [0..50] | IsPrime(a) where a is n^2+3*n+223 ]; // _Vincenzo Librandi_, Jul 14 2012

%Y Cf. A153423.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 26 2008