you can lock tables. So if you want a column of cells locked that column should be a table that is one column wide.
Then cells with formulas can refer to that table. If you have your table already set up where the input column and the formulas are in the same table, just select the user input column then click and hold on the column, then, when the column lifts off the table, drag the column out of the table, then lock the table with the formula.
to lock the table, select any cell in the table to activate it, then select the menu item "Arrange > Lock"