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Primes of the form 10n^2 + 9.
1

%I #6 Sep 08 2022 08:46:01

%S 19,499,1009,1699,8419,9619,14449,21169,24019,28099,30259,34819,38449,

%T 49009,53299,68899,84649,94099,102019,118819,141619,156259,169009,

%U 176899,184969,187699,240259,259219,268969,306259,309769,327619

%N Primes of the form 10n^2 + 9.

%H Vincenzo Librandi, <a href="/A201711/b201711.txt">Table of n, a(n) for n = 1..5000</a>

%t Select[Table[10n^2+9,{n,0,1000}],PrimeQ]

%o (Magma) [a: n in [0..300] | IsPrime(a) where a is 10*n^2+9];

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 04 2011