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A036932
Smallest n-digit prime containing only digits 1 and 5, or 0 if no such prime exists.
1
5, 11, 151, 1151, 11551, 115151, 1111151, 15511151, 111151511, 1111115111, 11111151551, 111111111511, 1111111155151, 11111111511151, 111111111155111, 1111111111155151, 11111111111115151, 111111111115151551
OFFSET
1,1
LINKS
MATHEMATICA
Table[SelectFirst[FromDigits/@Tuples[{1, 5}, n], PrimeQ], {n, 20}] (* Harvey P. Dale, Aug 04 2019 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Jan 04 1999
EXTENSIONS
Corrected by Harvey P. Dale, Mar 19 2013
STATUS
approved