none
1023456789
5
102
103
1,234,567
1023456789
10234567
5
5
10234567
0123456789
Since there are only five different digits, a 6-digit number can only be generated if a digit can be repeated. If digits can be repeated, the smallest 6-digit number is 111111.
5
102
103
100,000,000,000
The smallest number with no digits repeated would either be zero or one, depending on the set of numbers you want to choose from.