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%I #27 Sep 08 2022 08:45:31
%S 23,53,83,113,173,233,263,293,353,383,443,503,563,593,653,683,743,773,
%T 863,953,983,1013,1103,1163,1193,1223,1283,1373,1433,1493,1523,1553,
%U 1583,1613,1733,1823,1913,1973,2003,2063,2153,2213,2243,2273,2333,2393
%N Primes congruent to 23 (mod 30).
%C Primes (excluding 3) ending in 3 with (SOD-1)/3 non-integer where SOD is sum of digits. - _Ki Punches_
%C The sequence is infinite by Dirichlet's theorem. - _Arkadiusz Wesolowski_, Apr 02 2014
%C Terms are non-twin primes A007510. - _Omar E. Pol_, Jul 25 2019
%H Vincenzo Librandi, <a href="/A132235/b132235.txt">Table of n, a(n) for n = 1..1000</a>
%H C. K. Caldwell, <a href="http://primes.utm.com">The Prime Pages</a>.
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenes/cribade30columnas.jpg">Prime numbers in a sieve with 30 columns</a>
%F a(n) = A158791(n)*30 + 23. - _Ray Chandler_, Apr 07 2009
%F Intersection of A030431 and A007528. - _Ray Chandler_, Apr 07 2009
%t Select[Prime[Range[1000]],MemberQ[{23},Mod[#,30]]&] (* _Vincenzo Librandi_, Aug 14 2012 *)
%t Select[Range[23,2400,30],PrimeQ] (* _Harvey P. Dale_, Jan 27 2020 *)
%o (Magma) [p: p in PrimesUpTo(3000) | p mod 30 eq 23 ]; // _Vincenzo Librandi_, Aug 14 2012
%o (PARI) is(n)=isprime(n) && n%30==23 \\ _Charles R Greathouse IV_, Jul 01 2016
%Y Cf. A000040, A039949.
%Y Cf. A132230, A132231, A132232, A132233, A132234, A132236.
%K nonn,easy
%O 1,1
%A _Omar E. Pol_, Aug 15 2007
%E Extended by _Ray Chandler_, Apr 07 2009
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