Help please, on determining frame number start of a DNG clip

This is for a VFx roto workflow. I've never done it before so some help would be much appreciated.

I have a 4.6k DNG 3:1 clip that's been trimmed in the timeline.

I'd like to give the roto folks a 12 bit DPX sequence with the same frame label numbers as the source DNGs.

There doesn't seem to be any way I can see to determine the frame number of the first DNG frame in the edited clip, just its timecode.

Is there a way?

I found it. I kept looking for the drop down menu beside the viewer timecode, instead of clicking on the timecode.