For some of the TIP41 Transistors the pinout is not marked in the datasheet. In order to confirm the pinout you need to find the diagram for TO220-AB packages Style 1 on ON Semi’s website, linked here:
Hope this helps!
Applicable Part Numbers
TIP41-ND
TIP41AFS-ND
TIP41B-ND
TIP41C-ND
TIP41BTU-ND
TIP41CTU-ND