Everyone knows that if you select two cells with numbers and pull them into other cells then lined a series of numbers in arithmetic progressions. But it turns out the possibility Excel format are not limited to only one arithmetic progression. You can very easily customize the desired sequence. Moreover, it will be enough to enter only the first value, then take your mouse to the lower right corner to the formation of black cross. (Actually, the same as that in the ordinary filling). But pull down cells should left and not right mouse button! This will bring up a context menu where you select the last item "progression" And in the window, you can choose the type of progression (arithmetic, geometric) step, threshold, etc.
We will get: