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A178589
Smallest prime that is the average of the members of exactly n emirp pairs.
2
11311, 14741, 24547, 25447, 1427291, 2278277, 1551551, 2403487, 2477297, 2402537, 2512597, 123085271, 2509597, 124333421, 123974371, 133504831, 132954781, 135166981, 136545131, 134525431, 135955081, 135004981, 145475041
OFFSET
1,1
EXAMPLE
a(3) = 24547 is the first prime arithmetic mean of 3 emirp pairs, viz., (11083, 38011), (12073, 37021), (18013, 31081), followed by prime 27067, equidistant between members of each of the 3 emirp pairs (14593, 39541), (16573, 37561), (19543, 34591), and continues on with prime 42929, the average of exactly 3 other emirp pairs (10457, 75401), (11447, 74411), (12437, 73421), ...
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, May 29 2010
EXTENSIONS
Extended by Ray Chandler, Jul 05 2010
a(5)-a(23) from Donovan Johnson, Jul 06 2010
STATUS
approved