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A338410
Primes p such that (p+2)/3 and (p+3)/2 are prime.
2
7, 19, 31, 139, 199, 211, 379, 499, 631, 919, 1039, 1291, 1399, 1759, 2179, 2719, 2731, 2971, 3271, 3691, 4591, 5791, 5851, 6079, 7591, 8011, 8779, 10039, 11299, 11719, 11731, 12979, 14251, 15031, 15511, 15679, 18451, 18859, 20071, 21379, 21559, 22051, 22639, 23599, 24499, 24691, 25339, 25579
OFFSET
1,1
COMMENTS
All terms == 7 (mod 12).
LINKS
EXAMPLE
a(3) = 31 is in the sequence because 31, (31+2)/3 = 11 and ((31+3)/2) = 17 are prime.
MAPLE
filter:= t -> isprime(t) and isprime((t+2)/3) and isprime((t+3)/2):
select(filter, [seq(i, i=7..30000, 12)]);
MATHEMATICA
Select[Prime[Range[3000]], AllTrue[{(#+2)/3, (#+3)/2}, PrimeQ]&] (* Harvey P. Dale, May 20 2023 *)
PROG
(PARI) isok(p) = iferr(isprime(p) && isprime((p+2)/3) && isprime((p+3)/2), E, 0); \\ Michel Marcus, Oct 25 2020
CROSSREFS
Intersection of A091180 and A092109.
Sequence in context: A216564 A145042 A153892 * A038869 A147503 A147465
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Oct 25 2020
STATUS
approved