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A332674
Prime numbers p_k such that p_k == 1 (mod 10) and p_(k+1) == 9 (mod 10).
3
401, 491, 701, 761, 911, 1381, 1571, 2161, 2531, 2741, 2861, 2971, 3011, 3041, 3221, 3271, 3491, 3701, 3881, 4751, 5051, 5171, 6011, 6221, 6451, 6521, 6581, 7151, 7351, 7621, 7691, 8171, 8191, 8681, 8761, 8971, 9311, 9941, 10151, 10391, 10531, 10631, 10691
OFFSET
1,1
LINKS
R. J. Lemke Oliver and K. Soundararajan, Unexpected biases in the distribution of consecutive primes, arXiv:1603.03720 [math.NT], 2016.
R. J. Lemke Oliver and K. Soundararajan, Unexpected biases in the distribution of consecutive primes, Proceedings of the National Academy of Sciences of the United States of America, Vol. 113, No. 31 (2016), E4446-E4454.
MAPLE
select(p -> isprime(p) and nextprime(p) mod 10 = 9, [seq(i, i=1..20000, 10)]); # Robert Israel, Jun 10 2024
MATHEMATICA
First @ Transpose @ Select[Partition[Select[Range[12500], PrimeQ], 2, 1], Mod[First[#], 10] == 1 && Mod[Last[#], 10] == 9 &] (* Amiram Eldar, Feb 19 2020 *)
PROG
(PARI) forprime(p=1+o=2, 1e4, p%10==9&&o%10==1&&print1(o", "); o=p) \\ M. F. Hasler, Feb 19 2020
CROSSREFS
Cf. A030430 (1, any), A330366 (1, 1), A331555 (1, 3), A331324 (1, 7), this sequence (1, 9), A030431 (3, any), A332675 (3, 1), A332676 (3, 3), A030432 (7, any), A030433 (9, any) [where (a, b) means p_k == a (mod 10) and p_(k+1) == b (mod 10)].
Sequence in context: A159890 A029705 A096991 * A141026 A158313 A094614
KEYWORD
nonn
AUTHOR
A.H.M. Smeets, Feb 19 2020
STATUS
approved