The difference between the last three digits and the first three digits of an integer (decreasing greatly) can be divisible by 1 1.
Let's prove that 1111...11(Yes 199 1.
First, use the first 1988 digits, namely1111...11(including1650)
Get 1111...1000 (preceded by 1985 bits1). So this topic becomes:
If 1111...11(with 1985 bits1)
Then take out the first 1982 digits, namely1111...11(with 1982
Get 1111...1000 (including 1979 bits1), ...
After repeated application for 663 times, the attribute is finally converted into: 1 1, which can be divisible by 1 1.
To sum up,1111...11(with 199 1 bit.