You won't be able to do it with one AT command. I use the following approach when I need to schedule something hourly:

AT \\MyNTServerName 01:00 /interactive /every:M,T,W,Th,F,S,Su c:\temp\MyApp.exe
AT \\MyNTServerName 02:00 /interactive /every:M,T,W,Th,F,S,Su c:\temp\MyApp.exe
AT \\MyNTServerName 03:00 /interactive /every:M,T,W,Th,F,S,Su c:\temp\MyApp.exe
AT \\MyNTServerName 04:00 /interactive /every:M,T,W,Th,F,S,Su c:\temp\MyApp.exe

I didn't design the environment that I have to do this in. I never would have designed this to work this way. We are rewriting this to use a table driven approach. For now, we support it this way. We put all these AT commands into a CMD file and run it whenever there is a change. It is a maintenance headache. My advice to you is to think hard about alternatives.

Hope this helps.

Marty