A327748 Primes p such that the sum of p and the prime before p is not a multiple of 3.

3, 5, 29, 37, 53, 59, 67, 79, 89, 137, 157, 163, 173, 179, 211, 223, 239, 257, 263, 269, 277, 337, 359, 373, 379, 389, 439, 449, 479, 509, 521, 541, 547, 563, 569, 577, 593, 599, 607, 613, 631, 653, 659, 673, 683, 733, 739, 757, 809, 947, 953, 977, 983, 997

Offset

1,1

Comments

Apart from leading terms, similar to A151800(A258578). - Rémy Sigrist, Oct 02 2019

Except for the first two terms (3 and 5), this sequence also represents the primes such that (prime(n)^3 - prime(n-1)^3) is divisible by 3. - Jeff Brown, Jul 06 2020

Links

Table of n, a(n) for n=1..54.

Example

3 is in the sequence because the prime before 3 is 2, and 2 + 3 = 5, and 5 is not divisible by 3.
53 is in the sequence because the prime before 53 is 47, and 47 + 53 = 100, and 100 is not divisible by 3.

Mathematica

Select[Prime[Range[2, 168]], Mod[#+NextPrime[#, -1], 3]!=0&] (* Ivan N. Ianakiev, Oct 08 2019 *)

Prog

(PARI) isok(p) = isprime(p) && (p>2) && ((p+precprime(p-1)) % 3); \\ Michel Marcus, Oct 02 2019

Crossrefs

Cf. A000040, A008585.

Sequence in context: A355273 A361085 A141578 * A272345 A356147 A364762

Adjacent sequences: A327745 A327746 A327747 * A327749 A327750 A327751

Keyword

nonn

Author

Todor Szimeonov, Sep 23 2019

Status

approved