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A370156
Primes p such that (p-2)/3 is prime and 3*p+2 is composite.
1
11, 41, 53, 71, 113, 131, 179, 251, 311, 449, 491, 521, 593, 599, 683, 701, 719, 773, 809, 881, 941, 1049, 1061, 1103, 1151, 1229, 1301, 1319, 1373, 1439, 1499, 1511, 1571, 1709, 1733, 1931, 2273, 2309, 2393, 2579, 2591, 2663, 2843, 2861, 2903, 3041, 3119
OFFSET
1,1
EXAMPLE
(11-2)/3 is a prime and 3*11+2 isn't.
MATHEMATICA
Select[Prime[Range[500]], ! PrimeQ[3 # + 2] && PrimeQ[(# - 2)/3] &]
PROG
(PARI) isok(p) = if (isprime(p), !isprime(3*p+2) && (((p%3) == 2) && isprime((p-2)/3))); \\ Michel Marcus, Feb 17 2024
CROSSREFS
Cf. A000040, A115058 (supersequence), A023208, A370157.
Sequence in context: A065049 A158201 A350006 * A122015 A192820 A078653
KEYWORD
nonn
AUTHOR
Clark Kimberling, Feb 10 2024
STATUS
approved