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A072017
Numbers k such that gcd(k, reverse(k)) = 81 = 3^4, where reverse(x) = A004086(x).
1
2899999989, 2989999899, 2999889999, 3799999899, 3898989999, 3899799999, 3899999988, 3979989999, 3988899999, 3989999898, 3989999979, 3998999889, 3999889998, 3999898989, 3999899799, 3999979989, 3999988899, 4699998999
OFFSET
1,1
COMMENTS
Numerous solutions can be constructed by inserting strings of suitable digits between digits of terms in A071016.
LINKS
EXAMPLE
k = 3*3*3*3*3*449*64157 and reverse(k) = 2*2*3*3*3*3*31*67*14827, GCD = 81.
KEYWORD
nonn,base
AUTHOR
Labos Elemer, Jun 05 2002
STATUS
approved