OFFSET
1,1
COMMENTS
All terms > 7 (prime) are divisible by 3. Also note that n-4 and n+4 are not necessarily consecutive primes. First case when n-4 and n+4 are consecutive primes is for n=93 with n-4=89 and n+4=97. - Zak Seidov, Apr 22 2015
LINKS
Daniel Starodubtsev, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = A023202(n) + 4. - Michel Marcus, Apr 22 2015
MAPLE
ZL:=[]:for p from 1 to 1444 do if (isprime(p) and isprime(p+8) ) then ZL:=[op(ZL), (p+(p+8))/2]; fi; od; print(ZL); # Zerinvary Lajos, Mar 07 2007
MATHEMATICA
f[n_]:=PrimeQ[n-4]&&PrimeQ[n+4]; lst={}; Do[If[f[n], AppendTo[lst, n]], {n, 3, 8!, 2}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 09 2009 *)
Select[Prime[Range[250]], PrimeQ[#+8]&]+4 (* Harvey P. Dale, May 21 2023 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Sep 27 2003
EXTENSIONS
More terms from Ray Chandler, Oct 26 2003
STATUS
approved