Click and Drag not Calculating Properly

There's no way for it to know that the next cell should be 0 then 10... gotta go through enough iterations of the cycle to ensure that there can't be any other pattern for it to interprate.

Example: If I just showed you a sequence:
0, 0, 0, 5, 2, 7, 0, 2
What number should come next?

Preface this by saying that I almost never use the click and drag feature. In part because I guess I'm not quite sure how good the "pattern recognition algorithms" are. In general I prefer to make my own patterns like this from formulas -- if for no other reason than I distrust the built in pattern recognition stuff. The first example, it almost looks like Excel is "averaging" the 10 and 0's to get 3.33 (=10/3). For the second example, it looks like it is using a linear regression type algorithm (I can replicate the 2.2, 2.4,... using the TREND() function).

If Excel seems unable to recognize the pattern you want, then it would seem that you will have to create your own algorithm for generating the pattern. The second pattern could maybe be generated using something like (pseudocode of sorts - these aren't real formulas): =IF(row number is odd,1,2). The first pattern might look like =IF(both cells above are 0,10,0). Using a formula like this and you won't be dependent on Excel's pattern recognition algorithms. You'll be able to tell Excel what pattern to create.

hmm interesting ) you learn something new every day in here

or use a right-click and drag then choose copy instead of a fill option