===== Arithmetic structure of natural numbers ===== ==== Set ==== | @#FFBB00: definiendum | @#FFBB00: $\langle \mathbb N,+,\cdot \rangle$ | | $ m=S(k) $ | | @#55EE55: postulate | @#55EE55: $n + 0 = n$ | | @#55EE55: postulate | @#55EE55: $n + m = S(n) + k$ | | @#55EE55: postulate | @#55EE55: $n \cdot 0 = 0$ | | @#55EE55: postulate | @#55EE55: $n \cdot m = n + (n \cdot k) $ | ==== Discussion ==== >todo: rewrite the defintion in my current notation We'll often omit the multiplication sign. === Reference === [[http://en.wikipedia.org/wiki/Peano_axioms|Peano axioms]] ==== Parents ==== === Context === [[Successor set]] === Requirements === [[Natural number]] === Element of === [[Commutative semiring]] === Related === [[Cardinal arithmetic with types]]