Rename - Directory Opus

I'm having trouble finding a listing of the various syntax combinations of special characters, numbers, etc. for use in the File -> Rename command dialog. I have a list of filenames in one series that I want to rename in another series with a different "common" portion, as in:

scanA051 -> J-281001
scanA052 -> J-281002
scanA062 ->J-281012

I will be doing this sort of thing now and then. I seem to recall doing this before but I can't seem to figure it out now. Any advice would be appreciated.
Thank You.

Something like this maybe?

Yea, that's it. Where do I find (in Help) the list of possible syntax ie. [#]; #; /1; /2; etc.?

In the Appendix section near the back.

Also, you might want to search the Opus help for "sequential numbering" for an explanation about [#]