Sentence:  As the evolved solution for the first 16 <WSD>prime numbers</WSD> was capable of accepting inputs up to 31, we decided to extend the experiment to see how the solution generalised on 15 previously unseen inputs (just as we did with the integer-based approach). From the 15 unseen inputs, 7 of the predicted 15 outputs were <WSD>prime numbers</WSD>, which is just below 50%, indicating that the solution had learned something about "primeness" or favoured <WSD>prime numbers</WSD>. 
Meaning of the word marked with <WSD> tags:  Any natural number greater than 1 that is divisible only by itself and 1.