Leading zeros in Excel are always a problem.
Excel doesn't "see" leading zeros as part of a numeric value. By default
Excel drops leading zeros but you can force it to *DISPLAY* them using a
custom format. However, this is for *display purposes only*. You may see the
leading zeros but to Excel they do not exist.
With that in mind...
You need to list all the combinations of the number of interest.
123
132
231
213
321
312
Assume these numbers are in the range G1:G6
The numbers you want to highlight are in the range A1:A10
Select the range A1:A10
Goto the menu Format>Conditional Formatting
Select the Formula Is option
Enter this formula in the box on the right:
=MATCH(A1,G$1:G$6,0)
Click the Format button
Select the desired style(s)
OK out