A358565 a(n) = A358548(n) / 6.

1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 2, 1, 1, 3, 1, 2, 3, 1, 1, 2, 1, 5, 1, 1, 2, 1, 1, 1, 2, 2, 3, 1, 5, 1, 1, 4, 1, 2, 3, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 6, 1, 1, 3, 1, 1, 3, 4, 1, 1, 1, 3, 1, 3, 3, 4, 3, 2, 4, 2, 2, 1, 2, 3, 1, 3, 1, 4, 3, 2, 1, 1, 3, 1, 1, 5, 1

Offset: 2

Author

Jordan Gunter, Nov 22 2022

Keywords

• nonn

Comments

(1/6) * (first differences of consecutive primes of the form 3*k - 1).

Crossrefs

Cf. A358548, A003627.

Programs

Python

from itertools import islice
from sympy import isprime
def A358565_gen(): # generator of terms
    p, q = 5, 11
    while True:
        while not isprime(q):
            q += 3
        yield (q-p)//6
        p = q
        q += 3
A358565_list = list(islice(A358565_gen(),30)) # Chai Wah Wu, Jan 05 2023