OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
Do[If[(Prime[n + 6] + Prime[n])/2 == Prime[n + 3], Print[Prime[n + 3]]], {n, 1, 3000}]
Transpose[Select[Partition[Prime[Range[4000]], 7, 1], (First[#]+Last[#])/2==#[[4]]&]][[4]] (* Harvey P. Dale, Feb 16 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Dec 21 2006
EXTENSIONS
Extended by Ray Chandler, Dec 27 2006
STATUS
approved