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A104520
Smallest semiprime containing exactly n 1's.
0
10, 115, 111, 1111, 11111, 1111114, 1111111, 110111111, 1111111141, 11101111111, 11111111111, 1111111111101, 10111111111111, 111111011111111, 1111111111101111, 10111111111111111, 11111111111111111
OFFSET
1,1
EXAMPLE
a(2)=115 because 115 is the smallest semiprime containing exactly two 1's.
CROSSREFS
Sequence in context: A196983 A199908 A185391 * A138845 A079678 A233908
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 24 2005
STATUS
approved