This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A132230 Primes congruent to 1 (mod 30). 20
 31, 61, 151, 181, 211, 241, 271, 331, 421, 541, 571, 601, 631, 661, 691, 751, 811, 991, 1021, 1051, 1171, 1201, 1231, 1291, 1321, 1381, 1471, 1531, 1621, 1741, 1801, 1831, 1861, 1951, 2011, 2131, 2161, 2221, 2251, 2281, 2311, 2341, 2371, 2521, 2551, 2671 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Also primes congruent to 1 (mod 15). - N. J. A. Sloane, Jul 11 2008 Primes ending in 1 with (SOD-1)/3 integer where SOD is sum of digits. - Ki Punches, Feb 04 2009 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..10000 C. K. Caldwell, The Prime Pages. FORMULA a(n) = A111175(n)*30 + 1. - Ray Chandler, Apr 07 2009 Intersection of A030430 and A002476. - Ray Chandler, Apr 07 2009 EXAMPLE From Muniru A Asiru, Nov 01 2017: (Start) 31 is a prime and 31 = 30*1 + 1; 61 is a prime and 61 = 30*2 + 1; 151 is a prime and 151 = 30*5 + 1; 211 is a prime and 211 = 30*7 + 1; 241 is a prime and 241 = 30*8 + 1; 271 is a prime and 271 = 30*9 + 1. (End) MAPLE select(isprime, [seq(i, i=1..1000, 30)]); # Robert Israel, Jan 19 2016 MATHEMATICA Select[Range[1, 3000, 30], PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Feb 19 2012 *) PROG (PARI) is(n)=isprime(n) && n%30==1 \\ Charles R Greathouse IV, Jul 01 2016 (GAP) A132230 := Filtered(Filtered([1..10^6], n -> n mod 30 = 1), IsPrime); # Muniru A Asiru, Nov 01 2017 CROSSREFS Cf. A057204, A068228, A129805, A039949, A132231-A132236. Sequence in context: A054804 A128470 A195744 * A136066 A282326 A114991 Adjacent sequences:  A132227 A132228 A132229 * A132231 A132232 A132233 KEYWORD nonn,easy AUTHOR Omar E. Pol, Aug 15 2007 EXTENSIONS Edited by Ray Chandler, Apr 07 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 19 11:06 EDT 2019. Contains 327192 sequences. (Running on oeis4.)