It is not out of the ordinary to need to enter a series of numbers within a range of worksheet cells. For example, you may need to enter a series of numbers in the first ten columns of a certain row, or you may have a need to enter information just in a range of ten cells in a particular column.
To sequentially enter information in a range of cells, you should always first select your cells. You will notice that Excel will leave the top-left cell in the range as the input cell (it appears white and outlined). The rest of the cells in the range are shaded, to show that they have been selected.
Now all you need do is start entering your numbers. When you do, the value you keyed in is entered into the input cell. When you click Enter at the end of the value, Excel will save the value and move the input cell to the next cell in the selected range. Excel will move the input cell either left to right, top to bottom or top to bottom, left to right.
Good to know right?