OFFSET
1,2
COMMENTS
Zero together with A100319, the even numbers n such that at least one of n-1 and n+1 is composite.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
MATHEMATICA
Select[Range[0, 100], Mod[#, 2] == 0 && !PrimeQ[#] && (! PrimeQ[# - 1] || !PrimeQ[# + 1]) &] (* G. C. Greubel, Jul 07 2016 *)
Join[{0}, Select[Range[2, 150, 2], AnyTrue[#+{1, -1}, CompositeQ]&]] (* Harvey P. Dale, Nov 10 2024 *)
PROG
(PARI) isA167692(n) = (n%2==0)&&!isprime(n)&&(!isprime(n-1)||!isprime(n+1)) \\ Michael B. Porter, Feb 02 2010
CROSSREFS
KEYWORD
nonn,easy,less
AUTHOR
Juri-Stepan Gerasimov, Nov 09 2009
EXTENSIONS
Edited by Charles R Greathouse IV, Mar 22 2010
STATUS
approved