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Primes congruent to 7 mod 31.
1

%I #16 Sep 08 2022 08:45:35

%S 7,131,193,317,379,503,751,937,1061,1123,1433,1619,1867,2053,2239,

%T 2549,2797,3169,3541,3727,3851,4099,4409,4657,4967,5153,5711,5897,

%U 6269,6703,6827,7013,7757,8191,8377,8501,8563,9059,9431,9679,9803,10733,11353,12097

%N Primes congruent to 7 mod 31.

%H Vincenzo Librandi, <a href="/A142011/b142011.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[Range[7,20000,31],PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Apr 20 2011 *)

%o (Magma) [ p: p in PrimesUpTo(30000) | p mod 31 eq 7 ]; // _Vincenzo Librandi_, Apr 20 2011

%o (PARI) is(n)=isprime(n) && n%31==7 \\ _Charles R Greathouse IV_, Jul 03 2016

%Y Cf. A000040, A142005, A142006.

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_, Jul 11 2008