OFFSET
1,1
COMMENTS
Almost all natural numbers are members of this sequence.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1)=26 (24,25,27,28 are composite nearest neighbors), a(2)=34 (32,33,35,36 are composite nearest neighbors).
MATHEMATICA
Select[Range[6!], !PrimeQ[#]&&!PrimeQ[#-1]&&!PrimeQ[#+1]&&!PrimeQ[#-2]&&!PrimeQ[#+2]&] (* Vladimir Joseph Stephan Orlovsky, Dec 26 2010 *)
Flatten[Position[Partition[PrimeQ[Range[310]], 5, 1], _?(Union[#]=={False}&), {1}, Heads->False]]+2 (* Harvey P. Dale, Nov 01 2013 *)
PROG
(PARI) for(n=4, 1e4, if(n-precprime(n)>2&&nextprime(n)-n>2, print1(n", ")))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Juri-Stepan Gerasimov, Nov 10 2009
EXTENSIONS
Comment and program from Charles R Greathouse IV, Nov 12 2009
Corrected terms, Clark Kimberling and Joerg Arndt, Jun 24 2011.
STATUS
approved