Math Carnival

Aaargh—I missed it again! I suppose I should know better by now, but I sent in my entries (on time at least) via the blog carnival submission form. I have lost more carnival entries that way, but I still let myself be lured in by the ease of using a form, rather than writing a simple email by hand. Silly, lazy me.

Anyway, the latest Carnival of Mathematics is now open at a mispelt bog, with plenty of fun graphics and interesting things to read about.

Procrastinating blogger that I am, I missed two out of my three favorite blog carnivals this week. The Carnival of Mathematics XIV went up a full two days early at Vlorbik on Math Ed, featuring several interesting math articles for your browsing pleasure.

Here is a word for your vocabulary list: triskaidekaphilia. The 13th Carnival of Mathematics at Polymathematics features facts galore about the number 13, plus several math blog articles for your enjoyment.

To the Pythagorean mystics, 10 was the Sacred Tetractys, the number of the Universe, “the source and root of eternal nature.” 10 is the fourth triangular number, the sum of the first 4 positive integers:

The Carnival of Math: Tenth Edition is up at MathNotations, with most of the posts at the middle-to-secondary school level this time. There are too many interesting topics for me to play favorites. Be sure to check it out!

The ninth Carnival of Mathematics at JD2718 takes us on an alphabetical romp through the world of math blogging.

There is plenty for everyone this week, from elementary and secondary math education to logic and recreational puzzles—too many good articles to list individually, so click over there and read them for yourself!

The 120th Carnival of Education is now up and running at I Thought a Think. As always, a wide variety of interesting articles to browse. Enjoy!

Edited to add: Oops! I missed the 8th Carnival of Mathematics last week.
My favorite posts mostly came in pairs.

Two puzzles from MathNotations:
When Curves Collide
Going off on Tangents

Two brainteasers from SharpBrains:
The Unkindest Cut of All
The Really, Really, Really Big Number

Two mind-blowing infinity puzzles that were fun to read, even though I didn’t really understand the answers:
Cats in a Tree
Dogs in a Mineshaft

And the odd-one-out is a history post:
Calculators: Past, Present and Future

The new Carnival of Mathematics is up and running at Modulo Errors. Highlights for me included:

Teaching Math
One opinion about when to introduce formal arithmetic (workbooky math) to children. What is the opportunity cost of too-early mathematics?

Criss-Cross Multiplication
An algorithm for two-digit multiplication that is easier for mental math.

Party For Polyglots
A brain teaser puzzle, not too difficult.

Coloring Knots
A topological doodling project.

The math geeks have hit the town at the Second Carnival of Mathematics, which features a wide variety of articles to enjoy—many of which are admittedly over my head.

I liked these:

Puzzle: Is the spider hungry?

My Favourite Theorems 1 (Halting Problem)

The results are in!

It’s been a very busy few weeks, and I never got around to posting last week’s carnivals. Here are a couple of math-related posts from last week’s Carnival of Homeschooling:

How the four operations become two

Words of Wisdom from Reader’s Digest

And from the Carnival of Education:

Testing Higher Order Thinking Skills — Part Two

Mind Over Math — Believing It Makes It So