In short
Matthew did not intend to have exactly fourteen names in each section, but he did intend to put equal weight on each section of Israel’s history.
We are of the opinion that Matthew evidently did not strive to mention exactly three times fourteen names. But he did construct the survey of the history in such a way that it roughly expresses the equality of the three periods, also as regards the names.1
2 Abraham was the father of Isaac, and Isaac the father of Jacob, and Jacob the father of Judah and his brothers,