Natural Such a function represents a partial functionality on naturals, wherever the proof of even (n) can be seen being a precondition. With the Cambridge English Corpus There isn't a true difference between the standard initial-order objects from the mathematical discourse - for instance naturals, sets and so forth - https://naturalhealthproductindia.blogspot.com/2025/09/cureayu-top-ayurvedic-brand-for.html