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 A132231 Primes congruent to 7 (mod 30). 15
 7, 37, 67, 97, 127, 157, 277, 307, 337, 367, 397, 457, 487, 547, 577, 607, 727, 757, 787, 877, 907, 937, 967, 997, 1087, 1117, 1237, 1297, 1327, 1447, 1567, 1597, 1627, 1657, 1747, 1777, 1867, 1987, 2017, 2137, 2287, 2347, 2377, 2437, 2467, 2557, 2617, 2647 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Primes ending in 7 with (SOD-1)/3 integer where SOD is sum of digits. - Ki Punches, Feb 07 2009 Intersection of A030432 and A002476. - Ray Chandler, Apr 07 2009 Only from 4927 on, there are more composite numbers than primes in {7+30k}, see A227869. - M. F. Hasler, Nov 02 2013 Terms are non-twin primes A007510, except for 7. - Jonathan Sondow, Oct 27 2017 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 C. K. Caldwell, The Prime Pages Omar E. Pol, Prime numbers in a sieve with 30 columns Omar E. Pol, Sobre el patrón de los números primos FORMULA a(n) = A158573(n)*30 + 7. - Ray Chandler, Apr 07 2009 a(n) = A211890(4,n-1) for n <= 5. - Reinhard Zumkeller, Jul 13 2012 MATHEMATICA Select[30*Range[0, 100]+7, PrimeQ] (* Harvey P. Dale, Feb 01 2012 *) Select[Prime[Range[1000]], MemberQ[{7}, Mod[#, 30]]&] (* Vincenzo Librandi, Aug 14 2012 *) PROG (Haskell) a132231 n = a132231_list !! (n-1) a132231_list = [x | k <- [0..], let x = 30 * k + 7, a010051' x == 1] -- Reinhard Zumkeller, Jul 13 2012 (MAGMA) [p: p in PrimesUpTo(3000) | p mod 30 eq 7 ]; // Vincenzo Librandi, Aug 14 2012 (PARI) forstep(p=7, 1999, 30, isprime(p)&&print1(p", ")) \\ M. F. Hasler, Nov 02 2013 CROSSREFS Cf. A007510, A007528, A010051, A068229, A117047, A129807, A039949, A132230-A132236, A214360. Sequence in context: A123085 A128471 A168003 * A289353 A221982 A104915 Adjacent sequences:  A132228 A132229 A132230 * A132232 A132233 A132234 KEYWORD nonn,easy AUTHOR Omar E. Pol, Aug 15 2007 EXTENSIONS Extended by Ray Chandler, Apr 07 2009 STATUS approved

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Last modified May 7 10:32 EDT 2021. Contains 343650 sequences. (Running on oeis4.)