Are there any free programs or web services for reverse engineering a formula given a set of inputs and outputs?

Consider if had 3 columns of data. The first two numbers are inputs, and the last one is an output: 3,4,7 1,4,5 4,2,6

The outputs could be produced with simply a+b, but there could be many formulas that would give the same result of course. I am talking about data without any error or deviation, and I think the formula would only need basic operations(divide, multiply, add, sutbract) and possibly use one of floor/ceiling/round.