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A023202
Primes p such that p + 8 is also prime.
38
3, 5, 11, 23, 29, 53, 59, 71, 89, 101, 131, 149, 173, 191, 233, 263, 269, 359, 389, 401, 431, 449, 479, 491, 563, 569, 593, 599, 653, 683, 701, 719, 743, 761, 821, 911, 929, 983, 1013, 1031, 1061, 1109, 1163, 1193, 1223, 1229, 1283, 1289, 1319, 1373, 1439
OFFSET
1,1
COMMENTS
All terms > 3 are congruent to 5 mod 6 (observation by Zak Seidov in SeqFan). Thus each corresponding p + 8 is congruent to 1 mod 6. - Rick L. Shepherd, Mar 25 2023
LINKS
Matt C. Anderson, Table of n, a(n) for n = 1..10000 (terms 1..1000 from T. D. Noe, corrected by Sean A. Irvine and Georg Fischer)
A. Granville and G. Martin, Prime number races, arXiv:math/0408319 [math.NT], 2004.
Eric Weisstein's World of Mathematics, Twin Primes
MAPLE
select(n-> isprime(n) and isprime(n+8), [`$`(1..1500)]); # G. C. Greubel, Feb 07 2020
MATHEMATICA
Select[Range[1500], PrimeQ[#] && PrimeQ[#+8]&] (* Vladimir Joseph Stephan Orlovsky, Aug 29 2008 *)
Select[Prime[Range[250]], PrimeQ[#+8]&] (* Harvey P. Dale, Dec 24 2020 *)
PROG
(Magma) [n: n in [0..1500] | IsPrime(n) and IsPrime(n+8)]; // Vincenzo Librandi, Nov 20 2010
(PARI) is(n)=isprime(n)&&isprime(n+8) \\ Charles R Greathouse IV, Jul 01 2013
(Sage) [n for n in (1..1500) if is_prime(n) and is_prime(n+8)] # G. C. Greubel, Feb 07 2020
(GAP) Filtered([1..1500], k-> IsPrime(k) and IsPrime(k+8)) # G. C. Greubel, Feb 07 2020
CROSSREFS
Disjoint union of A007530, A031926, A049437, A049438.
Sequence in context: A275785 A106901 A154550 * A049436 A117010 A056874
KEYWORD
nonn,easy
STATUS
approved