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.
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
Keywords
Examples
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).
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..10000
Programs
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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
Extensions
More terms from Dmitry Kamenetsky, Nov 30 2009
Missing term 13553 inserted by Alois P. Heinz, Jan 03 2022
Comments