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A167840 Six-times-isolated primes: primes p such that none of p+-2, p+-4, p+-6, p+-8, p+-10 nor p+-12 are prime.

%I A167840 #19 Jan 03 2022 21:37:22
%S A167840 2,1847,2179,2503,2819,3137,3433,3967,4177,4621,4831,5623,5953,6637,
%T A167840 7283,7369,7393,7433,7621,7993,8039,8147,9257,9587,10753,11027,11197,
%U A167840 11213,11369,11657,13063,13367,13381,13537,13553,13649,13859,14107,14221,14369,14503
%N A167840 Six-times-isolated primes: primes p such that none of p+-2, p+-4, p+-6, p+-8, p+-10 nor p+-12 are prime.
%C A167840 Essentially the same as A137873. - _R. J. Mathar_, Dec 06 2009
%H A167840 Alois P. Heinz, <a href="/A167840/b167840.txt">Table of n, a(n) for n = 1..10000</a>
%e A167840 a(1)=2 (-10,-8,-6,-4,-2,0,4,6,8,10,12 are nonprimes);
%e A167840 a(2)=1847 (1835,1837,1839,1841,1843,1845,1849,1851,1853,1855,1857,1859 are nonprimes).
%p A167840 q:= p-> not ormap(isprime, [seq([p+i, p-i][], i=2..12, 2)]):
%p A167840 select(q, [ithprime(i)$i=1..2000])[];  # _Alois P. Heinz_, Jan 03 2022
%Y A167840 Cf. A000040, A137873, A167771, A167839.
%K A167840 nonn
%O A167840 1,1
%A A167840 _Juri-Stepan Gerasimov_, Nov 13 2009, Mar 26 2010
%E A167840 More terms from _Dmitry Kamenetsky_, Nov 30 2009
%E A167840 Missing term 13553 inserted by _Alois P. Heinz_, Jan 03 2022