Ex: =A1+A2 next cell down A3+A4 next cell down A5+A6, not A1+A2, A2+A3, A3+A4. I am trying to net cells, some are exact duplicates, some are not

As a more general solution to Scott's answer, the following formula variant doesn't need to start in row 1:
To use it, enter the formula in same row as the first data point, adjust the absolute cell references to point to the first data point, and Auto Fill the formula down. E.g. to get the sum of A2+A3, A4+A5, etc., put the formula in B2 and point it to "$A$2", and drag/fill the formula down. Similarly, to take the sum of three cells at a time (A1+A2+A3, A4+A5+A6, etc.), you can use



If you are just trying to solve the A1+A2, A3+A4, A5+A6 problem, here’s a solution: Enter
in cell A somewhat more general approach would be
or, equivalently,
which explicitly references the two cells separately. 


If the formula have some patterns (as per to your example =A1+A2, and then =A3+A4), then yes it is possible. If you put (for example on B1) = A1+A2 highlight both B1 and B2, and then click and drag the bottom right corner of B2 (it should show as a thicker box) and drag and it will follow the pattern you have set previously. If this is not to your need, you will need to update your questions with more details, and preferably some examples. 

