Dave,

With the exception of the "helper buttons" that add missing chromatic pitches, the scale on a triple row C row and single row C accordion are the same. Depending on the model, the triple row may have additional buttons toward the bottom of the instrument that give you some higher notes, but the basic layout is the same. And the triple row doesn't have the low-note G pull that's at the top of a single row. Some graphics to help you here:

http://www.delaguerre.com/delaguerre/pedagogy/3rowbacc/NotesAndScales.html

Russ

I think the tuning may be different. The Triple row would be in
equal temperment and the Cajun in an alternate tuning. That may
make some diffrence in trying to get that Cajun sound.

What do others think?.... Ed

The triple row needs to sound right over a larger range of keys than a single row. So, yes, tuning will be different. Its similar, but not as bad, as trying to get a cajun sound out of a piano accordion.