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%I #37 May 21 2021 15:55:22
%S 31,61,151,181,211,241,271,331,421,541,571,601,631,661,691,751,811,
%T 991,1021,1051,1171,1201,1231,1291,1321,1381,1471,1531,1621,1741,1801,
%U 1831,1861,1951,2011,2131,2161,2221,2251,2281,2311,2341,2371,2521,2551,2671
%N Primes congruent to 1 (mod 30).
%C Also primes congruent to 1 (mod 15). - _N. J. A. Sloane_, Jul 11 2008
%C Primes ending in 1 with (SOD-1)/3 integer where SOD is sum of digits. - _Ki Punches_, Feb 04 2009
%H Vincenzo Librandi, <a href="/A132230/b132230.txt">Table of n, a(n) for n = 1..10000</a>
%H C. K. Caldwell, <a href="http://primes.utm.edu">The Prime Pages</a>.
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>.
%F a(n) = A111175(n)*30 + 1. - _Ray Chandler_, Apr 07 2009
%F Intersection of A030430 and A002476. - _Ray Chandler_, Apr 07 2009
%e From _Muniru A Asiru_, Nov 01 2017: (Start)
%e 31 is a prime and 31 = 30*1 + 1;
%e 61 is a prime and 61 = 30*2 + 1;
%e 151 is a prime and 151 = 30*5 + 1;
%e 211 is a prime and 211 = 30*7 + 1;
%e 241 is a prime and 241 = 30*8 + 1;
%e 271 is a prime and 271 = 30*9 + 1.
%e (End)
%p select(isprime, [seq(i,i=1..1000,30)]); # _Robert Israel_, Jan 19 2016
%t Select[Range[1, 3000, 30], PrimeQ] (* _Vladimir Joseph Stephan Orlovsky_, Feb 19 2012 *)
%t Select[Prime[Range[400]],Mod[#,30]==1&] (* _Harvey P. Dale_, May 21 2021 *)
%o (PARI) is(n)=isprime(n) && n%30==1 \\ _Charles R Greathouse IV_, Jul 01 2016
%o (GAP) A132230 := Filtered(Filtered([1..10^6], n -> n mod 30 = 1), IsPrime); # _Muniru A Asiru_, Nov 01 2017
%Y Cf. A057204, A068228, A129805, A039949, A132231-A132236.
%K nonn,easy
%O 1,1
%A _Omar E. Pol_, Aug 15 2007
%E Edited by _Ray Chandler_, Apr 07 2009
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