Published January 10, 2012
blogs , mathematics , science , technology
Tags: blogs, Gary McGuire, mathematics, problem, puzzle, science, sudoku, technology
While you might just need a pencil and your brain to fill in this week’s Sudoku puzzle, an Irish mathematician used millions of hours of supercomputing time in order to solve an important open problem in the mathematics of Sudoku; the game that was initially popularized in Japan and involves filling up a 9×9 grid with the numbers 1 to 9 according to certain rules.
Read more @ SciTechDaily
Published October 1, 2009
education , mathematics
Tags: abstract algebra, Algebra, Analysis, graduate school, graduate studies, Graduate Texts in Mathematics, Hungerford, James Wilson, problem, solution, thesis, thesis adviser, Thomas Hungerford
For some reason, our Algebra prof gave us 40 problems to solve. They are all in the first chapter and review comprehensively what I’ve learned in past algebra and algebraic structures classes. Still, 40 exercises, that’s a lot. Seeing as Hungerford’s book is pretty much a reference for graduate students in algebra, I was looking around for solutions to all of the problems since I am unsure if our prof will give us any or if he will give us hints.
I found Dr. James Wilson’s book on Hungerford’s problem sets. It’s available for free here. If it’ no longer there, you can launch a google search and you should find it easily enough.
Part of me almost wants to print it out. It’s 167 pages long. At any copy shop, it will cost about $3 to print that out. That’s including binding. That’s really cool. It will help me out quite a bit. Luckily, I’ve seen most of the subject matter before, so it shouldn’t be a problem. The prof mentioned that he’d take our midterm exam out of this problem set. Sounds good to me. Midterms are in week 9 and we’ve just finished week 3.
Continue reading ‘GTM Hungerford’s Algebra vol 73†’
On Tuesday, I went out of a ride. I got as far as the staircase. My tubeless front tire was deflated and I didn’t have an adaptor to inflate it. It was inflated during my servicing that afternoon so I was a bit miffed with the whole thing.
I went back inside and ate some salmon sashimi that my wife had picked up earlier. As much as I love my bike, these recent mechanical failures are a bit annoying. Actually, I’m surprised that there haven’t been worse. The bike hasn’t been properly ridden since last year and I rode it hard last week. Hard enough to break the chain. I cheaply repaired it, not wanting to buy another new chain.
The tubeless tire was fixed easily by adding a tube. Now I understood why the owner told me that the back tire had a tube in it. The reason is that he pierced it and didn’t want to pay $200-$300 for a new one. I don’t know much about them, but I’ll buy a new set a bit later this summer.It makes sense to just buy a set of tubeless tires that are less knobby.
So yesterday, I got the adaptor for my pump, a very bright Taiwanese made headlight, that doubles as an LED flashlight. It’s very bright and has a wide beam. I also bout a Topeak Mini-18 tool in order to start putting together my tool pack.
My work place for the summer is a few kilometers away. It doesn’t make much sense to take my bike, but the way there is a bit hilly, so it might be a good idea to use this to train while using my bike as transport.
I’ve also started working full time with kids again and naturally, I’m under the weather. I caught a little cold and it’s just annoying to have the sniffles while it’s 35C outside. Oh well, can’t have everything.
Well, turns out that my derailleurs aren’t acting up. My chain is the culprit and it almost broke on my out tonight. I wanted to get a good set of miles under my belt to start the week off, but it looks like today will be my rest day, after clocking about 80kms over the weekend.
It’s too bad, because I felt like the ride would have eased some of the tension in my legs. There is nothing like powering through a hill or some other cyclists when you are really into it. I noticed that my neighbours are also cyclists. They’ve got a few lights, making it actually possible to train at night, if you know the path. I’ll get some lights later this week. Probably just a front light.
Anyway, tomorrow at lunch, I’ll head to my local shop to quickly take care of this issue once and for all. That way, I’ll be able to ride tomorrow evening, right before the sun completely sets.
In retrospect, I was lucky that the chain failed so early on. I was about 500m from my home. Anything more would have been really annoying. I could only pedal half a crank each time on my way back. It was slow going.