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A110788
Copies of 7 and 1 alternately such that every partial concatenation is a prime.
10
7, 1, 77, 1111, 77777, 1111111111, 77777777777777777777777, 111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111
OFFSET
1,1
EXAMPLE
7, 71, 7177, 71771111, ... are all prime.
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Aug 13 2005
EXTENSIONS
More terms from Joshua Zucker, Jan 11 2006
STATUS
approved