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A370157
Primes p such that both 3p+2 and (p-2)/3 are composite or 0.
1
2, 31, 47, 61, 67, 73, 101, 107, 109, 137, 151, 157, 181, 191, 193, 211, 223, 229, 241, 263, 271, 277, 281, 283, 307, 331, 347, 359, 373, 379, 389, 401, 421, 431, 443, 461, 463, 467, 487, 509, 541, 547, 557, 563, 571, 587, 601, 613, 617, 619, 631, 641, 647
OFFSET
1,1
MATHEMATICA
Select[Prime[Range[200]], ! 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, A370156.
Sequence in context: A193423 A241484 A235477 * A129900 A262834 A376205
KEYWORD
nonn
AUTHOR
Clark Kimberling, Feb 10 2024
STATUS
approved