The last Wednesday Hodgepodge, and Mama Squirrel's summer reading list

I have not Wednesday-Hodgepodged for awhile, but I'm glad I didn't miss this one: it's the last-ever Hodgepodge. (First time we participated: July 2015.)

1. What has been the highlight of your summer so far? (It's still summer, people!)

That would be the trip to the U.S. in July, which was a sort of working holiday, retreat and reunion all at once. Some of our family also had a nice one-day holiday on Lake Huron.

2. What do you wish you'd done more of this summer? Less of?

Eaten more peaches: the ones we had were amazing.

I spent half the summer finishing a spring-term online course, and then a couple more weeks working on a writing project. So I could say I wish I'd done less work, but I really don't wish that, because Things Got Done.

 3. Something you're looking forward to on your September calendar?

My fall term online course, Designing Curriculum for Adult Learners, starts today. (So I'm procrastinating by answering the Hodgepodge.)

 4. Best/favorite book you've read this summer?

In June, I finished two education textbooks, a book of Denise Levertov's poetry, and the business book Scrum, which I'm still pondering.

Here are my four favourite books from July, August, and the first few days in September (because it's still summer):

Ulin, David
The Lost Art of Reading: Why Books Matter in a Distracted Time

Walsh, Peter
Let It Go (about decluttering)

White, James Emery
A Mind for God

Willis, Connie
To Say Nothing of the Dog

 6. Insert your own random thought here. 

Our family has now been online for twenty years. Definitely a life-changing decision, to dial up that first connection. Our two youngest cannot remember life any other way. It's been good, bad, strange, useful, productive, time-wasting, annoying, and amazing by turns. Right now it means that I have to go and work on my online class.


Linked from The Wednesday Hodgepodge at From This Side of the Pond.

Math archives #5: What's the longest prime number? --with an update

First posted on November 11, 2011.  (11-11-11.  I just thought I'd mention that.)

What would we do without the Internet...

I mentioned recently that a quick check on the current population of Burundi--the subject of a French lesson--showed that there were way more people there than even the (fairly recent) teacher's guide suggested.  That lined up with the fact that we were heading for 7 billion people on Earth by the end of last month.

Today's math history lesson was about the Sieve of Eratosthenes, and the hunt for very large prime numbers.  John Tiner's 2001 book Exploring the World of Mathematics mentioned that the largest discovered to date was over 4 million digits long, which would take about a thousand pages to print out.

On a hunch that that fact too might have been updated, I looked it up.

Yes, the 4-million-digits longest prime was correct in 2001.  

But as of 2008, we are up to a number that is 12,978,189 digits long.

And you thought your ID numbers were hard to learn.

2014 Update from Wikipedia:  As of January 2014, the largest known prime number is 2^57,885,161 − 1, a number with 17,425,170 digits.  (Sourced from this article.)