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A301918
Primes which divide numbers of the form 3^k+3.
1
2, 3, 5, 7, 17, 19, 29, 31, 37, 41, 43, 53, 61, 67, 73, 79, 89, 97, 101, 103, 113, 127, 137, 139, 149, 151, 157, 163, 173, 193, 197, 199, 211, 223, 233, 241, 257, 269, 271, 281, 283, 293, 307, 317, 331, 337, 349, 353, 367, 373, 379, 389, 397, 401, 409, 439
OFFSET
1,1
COMMENTS
Union of {3} and A301916, because 3^k + 3 = 3*(3^(k-1) + 1). [Comment edited by Jeppe Stig Nielsen, Jul 04 2020.]
Can be used to factor P+1 values where P is a potential prime of the form 3^k+2.
Is this 2 and 3 with A045318? - David A. Corneth, May 04 2018
No, it is not. Primes like 769, 1297, ... are also here but not in A045318. See A320481 for the explanation. - Jeppe Stig Nielsen, Jun 27 2020
EXAMPLE
All values of 3^k+3 are multiples of 2, so 2 is in the sequence.
3^4+3 = 84, which is a multiple of 7, so 7 is in the sequence.
CROSSREFS
KEYWORD
nonn
AUTHOR
Luke W. Richards, Mar 28 2018
STATUS
approved