A370157 Primes p such that both 3p+2 and (p-2)/3 are composite or 0.

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

Links

Table of n, a(n) for n=1..53.

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 A229206

Adjacent sequences: A370154 A370155 A370156 * A370158 A370159 A370160

Keyword

nonn

Author

Clark Kimberling, Feb 10 2024

Status

approved