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Primes congruent to 16 mod 25.
1

%I #14 Sep 08 2022 08:45:35

%S 41,191,241,491,541,641,691,941,991,1091,1291,1741,2141,2341,2441,

%T 2591,2741,2791,3041,3191,3391,3491,3541,3691,4091,4241,4391,4441,

%U 4591,4691,5441,5591,5641,5741,5791,6091,6491,6691,6791,6841,6991,7541,7591,7691

%N Primes congruent to 16 mod 25.

%H Vincenzo Librandi, <a href="/A141939/b141939.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ 20n log n. - _Charles R Greathouse IV_, Jul 03 2016

%t Select[Range[16, 20000, 25], PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Jun 15 2011 *)

%t Select[Prime[Range[1000]],Mod[#,25]==16&] (* _Harvey P. Dale_, Aug 04 2022 *)

%o (Magma) [p: p in PrimesUpTo(8000) | p mod 25 eq 16 ]; // _Vincenzo Librandi_, Aug 16 2012

%o (PARI) is(n)=isprime(n) && n%25==16 \\ _Charles R Greathouse IV_, Jul 03 2016

%Y Cf. A000040.

%K nonn,easy

%O 1,1

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