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

%I A327748 #42 Apr 27 2025 01:08:12
%S A327748 3,5,29,37,53,59,67,79,89,137,157,163,173,179,211,223,239,257,263,269,
%T A327748 277,337,359,373,379,389,439,449,479,509,521,541,547,563,569,577,593,
%U A327748 599,607,613,631,653,659,673,683,733,739,757,809,947,953,977,983,997
%N A327748 Primes p such that the sum of p and the prime before p is not a multiple of 3.
%C A327748 Apart from leading terms, similar to A151800(A258578). - _Rémy Sigrist_, Oct 02 2019
%C A327748 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
%H A327748 Jason Bard, <a href="/A327748/b327748.txt">Table of n, a(n) for n = 1..10000</a>
%e A327748 3 is in the sequence because the prime before 3 is 2, and 2 + 3 = 5, and 5 is not divisible by 3.
%e A327748 53 is in the sequence because the prime before 53 is 47, and 47 + 53 = 100, and 100 is not divisible by 3.
%t A327748 Select[Prime[Range[2,168]],Mod[#+NextPrime[#,-1],3]!=0&] (* _Ivan N. Ianakiev_, Oct 08 2019 *)
%o A327748 (PARI) isok(p) = isprime(p) && (p>2) && ((p+precprime(p-1)) % 3); \\ _Michel Marcus_, Oct 02 2019
%Y A327748 Cf. A000040, A008585.
%K A327748 nonn
%O A327748 1,1
%A A327748 _Todor Szimeonov_, Sep 23 2019