The 2020 Invariants Michaelmas Puzzle Challenge is underway! Check out the problems below and look through our archives for previous problems and solutions!
Solutions should be submitted to firstname.lastname@example.org no later than 14:59 BST on the Sunday after they are posted. Please quote your name, your institution, the week, and the numbers of the problems attempted in the subject line, e.g. Septus Quizonacci - University of Oxford - Week 7 - Problems 1,2,3.