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%I #16 Sep 08 2022 08:45:35
%S 71,257,443,691,877,1063,1187,1249,1373,1559,1621,1931,1993,2179,2551,
%T 2861,3109,3853,4349,4597,4721,4783,4969,5279,5527,5651,6271,6581,
%U 6829,7573,7759,7883,8069,8317,8627,8689,8999,9371,9433,9619,9743,9929,10177,10301
%N Primes congruent to 9 mod 31.
%H Vincenzo Librandi, <a href="/A142013/b142013.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ 30n log n. - _Charles R Greathouse IV_, Jul 03 2016
%t Select[Prime[Range[1500]],Mod[#,31]==9&] (* _Harvey P. Dale_, Jan 27 2011 *)
%o (Magma)[ p: p in PrimesUpTo(17400) | p mod 31 in {9} ] // _Vincenzo Librandi_, Jan 28 2011
%o (PARI) is(n)=isprime(n) && n%31==9 \\ _Charles R Greathouse IV_, Jul 03 2016
%Y Cf. A000040.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jul 11 2008