EDB — 03H

Exercises

1. [03H] Found a polynomial $p(x,y)$ which, seen as a function $p:{\mathbb{N}}^2\to \mathbb{N}$ is bijective. It follows, iterating, that there is a polynomial $q_k$ in $k$ variables $q_k:{\mathbb{N}}^k\to \mathbb{N}$ that is bijective. So ${\mathbb{N}}^k$ is countable.

   Solution 1

   [03J]↺↻