Spring 2019

# prep

## Mon 21st Jan

Read Intransitive Dice by Conrey, Gabbard, Grant, Liu and Morrison. Don't worry about bits you don't understand.

## Wed 23rd Jan

Try to narrow down the range of possible values for the chromatic number of the plane.

## Mon 28th Jan

Read about counting. Choose a chapter called something like that from a book and get stuck in. Good words/phrases to look for: permutations, combinations, binomial coefficients, inclusion/exclusion, pigeonhole principle. Also good words, but mostly more advanced topics: asymptotics, recurrence relations, generating functions, derangements, catalan numbers, stirling numbers,... Come to class with one exercise that you've done to share with everyone. Aim for something at the trickier end of the ones you tried.

## Wed 30th Jan

Same as 28th, but further on from where you've reached. Perhaps other things TBD depending on how Monday goes.

## Mon 4th Feb

Counting wrap-up. Like last Monday, come with a problem and solution (and maybe some theory) to share.

## Wed 6th Feb

Intro to Graph Theory. No prep, but you the counting assignment due on Friday.

## Mon 11th Feb

• Proving the Five Colour Theorem
• Intro to Infinity

No specific prep, but you should be working through a graph theory chapter or two, ready for...

## Wed 13th Feb

Come with a graph theory result/exercise to show off.

## Mon 18th Feb

Come with another graph theory result/exercise to show off.

## Wed 20th Feb

Just for a change, come with a graph theory result/exercise to show off.

## Mon 25th Feb

There's a cardinal in that tree! An arboro-ornithological introduction to infinite graph theory. (No prep required, but remember to have submitted the second assignment, due on the 22nd.)

## Wed 27th Feb

Critical Sets in Latin Squares: Finite and Infinite. This will set the scene for the first possible group research project that we have in mind.

## Week of 4th Mar

First set of meetings (more details in class). Schedule:

• Mon, 11.30am-12.10pm: Kenny
• Mon, 12.10-12.50pm: William
• Wed, 11.30am-12.10pm: Kat
• Wed, 12.10-12.50pm: Aaron
• ???: Della

## Mon 25th Mar

Welcome back. We'll plan for the second half of the semester.

## Wed 27th Mar

Work on whatever topic you selected on Monday. Come with something to share.

## Week of 1st Apr

Mix of students presenting and group work on the infinite latin square project. Assignment due on Friday.

## Week of 8th Apr

Infinite latin squares and other combinatorial adventures. You should be working on your topics outside class, but nothing to prep for the classtime itself (except possibly some small bits between Monday and Wednesday, depending on exactly what we do in class on Monday).

## Week of 15th Apr

Kaethe and Matt will ask you to prepare to present problems, but in fact will hijack both sessions for their own nefarious ends and edit this page afterwards to make it look like that was the plan all along.

## Week of 22nd Apr

Have problems to present for real this time, on Monday at least. On Thursday (1.50pm, Sci217) we'll Zoom in to the Northeast Combinatorics Network's webcast talk by Peter Cameron. Part of Wednesday will be Kaethe and/or Matt prepping some material to help us understand that, but there might be time for one of you to share work then too.

## Week of 29th Apr

If you didn't present anything last week, there will be time to do so this week. As well as this, polishing up your final submissions is a good idea. Draft due on Wednesday and Matt and Kaethe will get you some feedback by Friday.

## Final Meetings

Meetings in Sci217, May 7th.

Aaron: 12.30pm w/Miha
Della: 10am w/Onur
Kat: 1.30pm  w/Miha
Kenny: 11am  w/Sara
William: 9am w/Onur

https://cs.marlboro.college /cours /spring2019 /discrete_math /prep