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A126242
Prime numbers p such that p = prime(n+4)=(prime(n+8)+prime(n))/2.
1
41, 61, 71, 89, 181, 373, 397, 433, 449, 863, 907, 911, 937, 941, 983, 1193, 1259, 1931, 2243, 2251, 2447, 3359, 3361, 3823, 3851, 4057, 4093, 5231, 5297, 5417, 5813, 6421, 6619, 7013, 7151, 7487, 7583, 7907, 8171, 8537, 8563, 8573, 8581, 9157, 9257, 9377
OFFSET
1,1
LINKS
MATHEMATICA
Do[If[(Prime[n + 8] + Prime[n])/2 == Prime[n + 4], Print[Prime[n + 4]]], {n, 1, 3000}]
Transpose[Select[Partition[Prime[Range[1200]], 9, 1], (First[#]+Last[#])/2 == #[[5]]&]][[5]] (* Harvey P. Dale, Jul 18 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Dec 21 2006
EXTENSIONS
Extended by Ray Chandler, Dec 27 2006
STATUS
approved