LftCM2020: Natural number game - Kevin Buzzard

In this talk, Kevin Buzzard introduces the natural number game.
Links:
1) pdf slides: wwwf.imperial.ac.uk/~buzzard/...
2) Natural number game: wwwf.imperial.ac.uk/~buzzard/...
3) A tactic cheat sheet: github.com/kbuzzard/xena/blob...