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A320752 Primes of the form 5*n^2 - 5*n + 13. 1

%I

%S 13,23,43,73,113,163,223,293,373,463,563,673,1063,1213,1373,1543,1723,

%T 1913,2113,2543,3793,4073,4363,4663,4973,5623,6673,7043,8623,9043,

%U 9473,12263,12763,14323,15413,15973,17123,17713,18313,19543,20173,22123,23473,26293

%N Primes of the form 5*n^2 - 5*n + 13.

%C The first 12 numbers of the form 5*n^2 - 5*n + 13 (n=1 to 12) are primes.

%H Harvey P. Dale, <a href="/A320752/b320752.txt">Table of n, a(n) for n = 1..1000</a>

%p select(isprime,[seq(5*n^2-5*n+13,n=1..75)]); # _Muniru A Asiru_, Oct 21 2018

%t Select[Table[5n^2-5n+13,{n,80}],PrimeQ] (* _Harvey P. Dale_, Aug 22 2021 *)

%o (PARI) terms(n) = my(i=0); for(k=1, oo, my(x=5*k^2-5*k+13); if(ispseudoprime(x), print1(x, ", "); i++); if(i==n, break))

%o /* Print initial 50 terms as follows */

%o terms(50) \\ _Felix Fröhlich_, Oct 20 2018

%o (GAP) Filtered(List([1..75],n->5*n^2-5*n+13),IsPrime); # _Muniru A Asiru_, Oct 21 2018

%Y Cf. A090562.

%K nonn

%O 1,1

%A _Arashdeep Singh_, Oct 20 2018

%E More terms from _Felix Fröhlich_, Oct 20 2018

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Last modified September 26 09:15 EDT 2021. Contains 347664 sequences. (Running on oeis4.)