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Primes congruent to 20 mod 23.
4

%I #12 Sep 08 2022 08:45:35

%S 43,89,181,227,457,503,641,733,1009,1193,1423,1607,1699,2113,2251,

%T 2297,2389,2711,2803,3079,3217,3539,3631,3677,3769,3907,4091,4229,

%U 4597,4643,4919,5011,5333,5471,5563,5701,5839,6299,6529,7127,7219,7541,7817,8093

%N Primes congruent to 20 mod 23.

%H Vincenzo Librandi, <a href="/A141924/b141924.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) ~ 22n log n. - _Charles R Greathouse IV_, Jul 02 2016

%t Select[Range[20,20000,23],PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, May 18 2011 *)

%o (Magma) [p: p in PrimesUpTo(9000) | p mod 23 eq 20 ]; // _Vincenzo Librandi_, Aug 16 2012

%o (PARI) is(n)=isprime(n) && n%23==20 \\ _Charles R Greathouse IV_, Jul 02 2016

%Y Cf. A000040, A141925, A141926.

%K nonn,easy

%O 1,1

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