What is a Leap Year?

I was going to answer this question myself, but then @Ms_Elevator posted a link to this, which does it better.

The Actual Maths

The Alan Turing Cryptography Competition - Each year, starting towards the end of January, the maths department at the University of Manchester release their Alan Turing Cryptography Competition i...
◼️ Tom⇒maths

How to Use a Spreadsheet to Batch-Upload Events to Your Calendar - The other day I posted... One of my favourite things I've discovered this year is using a spreadsheet to batch-add things to my calendar. Such a timesaver!...