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A090535
Least n-digit prime using digit 7 once and rest all 1, or 0 if no such prime exists.
3
7, 17, 0, 1117, 11117, 0, 1111711, 11111117, 0, 1117111111, 17111111111, 0, 1111171111111, 0, 0, 0, 11111111111111171, 0, 1111111111111111171, 11111111111111117111, 0, 1111111111111111111711, 11111111111111111111117
OFFSET
1,1
COMMENTS
a(3n) = 0.
EXAMPLE
a(5) = 11117.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Dec 08 2003
EXTENSIONS
More terms from David Wasserman, Jan 03 2006
STATUS
approved