OFFSET
1,2
COMMENTS
The positive integer n belongs to the sequence iff there exists a positive integer k so that each of the first k multiples of n contains the decimal digit 1, but no smaller n has this property for the same value of k.
EXAMPLE
51 is a term because the first three multiples of 51 (51, 102, 153) all contain the digit 1, and 51 is the least positive integer with this property.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
David Radcliffe, Sep 22 2018
STATUS
approved