iPad Factory Reset Without iTunes I have a 4th gen iPad that I haven't used for so long that I forgot the PIN.  I  want to restore it to factory defaults as I plan to use it again.  Everything I'm finding on this topic suggests that I need to use iTunes on a computer to accomplish this.  Is this actually the case?  Can't I use some combination of powering off/powering on and physical buttons to accomplish the same thing?
No amount of button pushing reloads the OS. 

You can try to brute force the pin, you can try to log in if you already have jail broken the device, the only option to bypass the pin is to connect to USB and have iTunes or a similar sophisticated program speak with the firmware. 

Once you've loaded things with iTunes (or substitute) then you have to deal with activation lock if you have that enabled.