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A142372
Primes congruent to 21 mod 47.
1
397, 491, 773, 1619, 1901, 2089, 2371, 3217, 3499, 3593, 4157, 4721, 4909, 5003, 5849, 6037, 6131, 6883, 6977, 7541, 7823, 8011, 8293, 8387, 8669, 8951, 9421, 10079, 10267, 10831, 11113, 11489, 11677, 11959, 12241, 12899, 13463, 13933, 14591, 14779, 15061
OFFSET
1,1
LINKS
FORMULA
a(n) ~ 46n log n. - Charles R Greathouse IV, Jul 03 2016
MATHEMATICA
Select[Prime[Range[2500]], MemberQ[{21}, Mod[#, 47]]&] (* Vincenzo Librandi, Aug 27 2012 *)
Select[Range[21, 16000, 47], PrimeQ] (* Harvey P. Dale, Jul 22 2016 *)
PROG
(Magma) [p: p in PrimesUpTo(18000) | p mod 47 eq 21]; // Vincenzo Librandi, Aug 27 2012
(PARI) is(n)=isprime(n) && n%47==21 \\ Charles R Greathouse IV, Jul 03 2016
CROSSREFS
Cf. A000040.
Sequence in context: A074483 A023326 A139385 * A341187 A038660 A129190
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jul 11 2008
STATUS
approved