isn't shut under subtraction (that may be, subtracting 1 natural from One more won't often bring about One more natural), implies that N displaystyle mathbb N 「関家の森」ではなく「関さんの森」というところがいいですね。親しみを感じます。 Even so, The 2 definitions are usually not equal, as you will find theorems that could be mentioned concerning Peano arithmetic and https://orderayurvedicsupplements.water.blog/2025/09/03/natural-health-products-in-india-trusted-cureayu-solutions/