The honest answer is between 500 and 500,000, and which end you are at depends almost entirely on whether you are teaching behaviour or coverage. Fortunately the question is cheap to answer empirically, and the procedure at the end of this page is worth more than any number. Why the number is unanswerable as asked “How many examples” conflates two quantities that behave completely differently. One is how many examples it takes for the model to learn the pattern — the output sha...