## Number systems

This theme grew from the film "The Story of 1" narrated by Terry Jones of Monty Python fame, which we showed the students in the middle of the week. We looked at counting in binary, helped by the Mathematica applets Binary Card Game (you may have seen this in a Christmas cracker!), Counting in Binary, and Binary Counting Sequence.

The story of Pythagoras and his denial of irrational numbers was discussed, and the existence of irrational numbers was proved using this Geogebra applet: