Natural This type of function represents a partial function on naturals, in which the proof of even (n) could possibly be observed to be a precondition. In the Cambridge English Corpus There isn't a true distinction between the usual to start with-order objects of the mathematical discourse - such as https://buyherbalmedicinesonline.politics.blog/2025/08/18/best-ayurvedic-brand-in-india-discover-cureayu-health-products/