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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.
1
2, 1847, 2179, 2503, 2819, 3137, 3433, 3967, 4177, 4621, 4831, 5623, 5953, 6637, 7283, 7369, 7393, 7433, 7621, 7993, 8039, 8147, 9257, 9587, 10753, 11027, 11197, 11213, 11369, 11657, 13063, 13367, 13381, 13537, 13553, 13649, 13859, 14107, 14221, 14369, 14503
OFFSET
1,1
COMMENTS
Essentially the same as A137873. - R. J. Mathar, Dec 06 2009
LINKS
EXAMPLE
a(1)=2 (-10,-8,-6,-4,-2,0,4,6,8,10,12 are nonprimes);
a(2)=1847 (1835,1837,1839,1841,1843,1845,1849,1851,1853,1855,1857,1859 are nonprimes).
MAPLE
q:= p-> not ormap(isprime, [seq([p+i, p-i][], i=2..12, 2)]):
select(q, [ithprime(i)$i=1..2000])[]; # Alois P. Heinz, Jan 03 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Nov 13 2009, Mar 26 2010
EXTENSIONS
More terms from Dmitry Kamenetsky, Nov 30 2009
Missing term 13553 inserted by Alois P. Heinz, Jan 03 2022
STATUS
approved