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A320752
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Primes of the form 5*n^2 - 5*n + 13.
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1
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13, 23, 43, 73, 113, 163, 223, 293, 373, 463, 563, 673, 1063, 1213, 1373, 1543, 1723, 1913, 2113, 2543, 3793, 4073, 4363, 4663, 4973, 5623, 6673, 7043, 8623, 9043, 9473, 12263, 12763, 14323, 15413, 15973, 17123, 17713, 18313, 19543, 20173, 22123, 23473, 26293
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OFFSET
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1,1
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COMMENTS
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The first 12 numbers of the form 5*n^2 - 5*n + 13 (n=1 to 12) are primes.
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LINKS
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MAPLE
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select(isprime, [seq(5*n^2-5*n+13, n=1..75)]); # Muniru A Asiru, Oct 21 2018
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MATHEMATICA
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Select[Table[5n^2-5n+13, {n, 80}], PrimeQ] (* Harvey P. Dale, Aug 22 2021 *)
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PROG
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(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))
/* Print initial 50 terms as follows */
(GAP) Filtered(List([1..75], n->5*n^2-5*n+13), IsPrime); # Muniru A Asiru, Oct 21 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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