A6 and A7 are floating pins. using open floating pins just needs a resistor value to them. and setup a library to set pin A6, A7 as input. If the floating pins are used it should be stated in doc or other documents related to their value as floating pin assignments.
A6 and A7 are 100% analog only pins and they are only available onboards with the surface mount version of the ATmega328.Don't try to treat them as digital inputs.
Finally we get somewhere. I know they are analog pins. I am going to treat them kindly. I did however ask if they are reserved for other function or devices. I have seen pins like this left to float for debugging hardware/software issues. My concern is are they free to use, or involved in other devices not spoken about in the past.