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%I #21 Feb 12 2020 01:47:57
%S 23,53,131,173,233,263,563,593,653,1013,1223,1283,1601,1613,2333,2543,
%T 2963,3323,3533,3761,3911,3923,4013,4211,4253,4643,4793,5003,5273,
%U 5471,5843,5861,6263,6353,6563,6653,6863,7121,7451,7481,7541,7583
%N p, p+6 and p+8 are all primes (A046138) but p+2 is not.
%H R. J. Mathar, <a href="/A049438/b049438.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Prime@ Range[10^3], MatchQ[Boole@ PrimeQ@ {# + 2, # + 6, # + 8}, {0, 1, 1}] &] (* _Michael De Vlieger_, Feb 05 2017 *)
%o (PARI) isok(p) = isprime(p) && !isprime(p+2) && isprime(p+6) && isprime(p+8); \\ _Michel Marcus_, Dec 13 2013
%Y Subsequence of A031924. - _R. J. Mathar_, Jun 15 2013
%Y Cf. A007530, A023202, A031926, A046134, A046138, A049436, A049437.
%K nonn,easy
%O 1,1
%A _Labos Elemer_
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