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A030431 Primes of form 10n+3. 21
3, 13, 23, 43, 53, 73, 83, 103, 113, 163, 173, 193, 223, 233, 263, 283, 293, 313, 353, 373, 383, 433, 443, 463, 503, 523, 563, 593, 613, 643, 653, 673, 683, 733, 743, 773, 823, 853, 863, 883, 953, 983, 1013, 1033, 1063, 1093, 1103, 1123, 1153, 1163, 1193 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also primes of form 5n+3.

Union of A132233, A132235, {3}. [Ray Chandler, Apr 07 2009]

Primes p such that arithmetic mean of divisors of p^4 is an integer. There are 2 such sequences of primes, this one and A030430. [Ctibor O. Zizka, Oct 20 2009]

5 is not quadratic residue of primes of this form. - Vincenzo Librandi, Jun 25 2014

LINKS

Michael B. Porter, Table of n, a(n) for n = 0..100000

A. Granville and G. Martin, Prime number races

FORMULA

a(n) = 10*A102338(n) + 3.

MATHEMATICA

Select[Prime@Range[200], Mod[ #, 10] == 3 &] (* Ray Chandler *)

Select[10 Range[0, 150] + 3, PrimeQ]  (* Harvey P. Dale, Apr 06 2011 *)

CROSSREFS

Cf. A045414, A049508, A102338.

Sequence in context: A121756 A178825 A147473 * A090146 A133313 A230026

Adjacent sequences:  A030428 A030429 A030430 * A030432 A030433 A030434

KEYWORD

nonn

AUTHOR

Warut Roonguthai

EXTENSIONS

Extended by Ray Chandler, Nov 07 2006

STATUS

approved

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Last modified December 22 22:37 EST 2014. Contains 252372 sequences.