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A142192
Primes congruent to 23 mod 40.
2
23, 103, 223, 263, 383, 463, 503, 743, 823, 863, 983, 1063, 1103, 1223, 1303, 1423, 1543, 1583, 1663, 1783, 1823, 2063, 2143, 2383, 2423, 2503, 2543, 2663, 2903, 3023, 3343, 3463, 3583, 3623, 3823, 3863, 3943, 4423, 4463, 4583, 4663, 4703, 4783, 4903, 4943
OFFSET
1,1
LINKS
FORMULA
a(n) ~ 16n log n. - Charles R Greathouse IV, Jul 02 2016
MATHEMATICA
Select[Prime[Range[2000]], MemberQ[{23}, Mod[#, 40]]&] (* Vincenzo Librandi, Aug 22 2012 *)
Select[Range[23, 5000, 40], PrimeQ] (* Harvey P. Dale, Apr 22 2018 *)
PROG
(Magma) [p: p in PrimesUpTo(6000) | p mod 40 eq 23 ]; // Vincenzo Librandi, Aug 22 2012
(PARI) is(n)=isprime(n) && n%40==23 \\ Charles R Greathouse IV, Jul 02 2016
CROSSREFS
Cf. A000040.
Sequence in context: A214092 A139976 A241746 * A129918 A240839 A138715
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jul 11 2008
STATUS
approved