Based on the data of the table, you can notice that the following function f(x):
f(x) = x + 4
represents the relation in between the values of the columns of the table.
For instance, you have:
f(3) = 3 + 4 = 7
f(4) = 4 + 4 = 8
f(5) = 5 + 4 = 9
f(6) = 6 + 4 = 10