# Math Teachers at Play #68 via Mathematical Mischief

[Photo by U.S. Army RDECOM CERDEC (CC BY 2.0) via Flickr.]

The Math Teachers at Play blog carnival is a monthly blogging round-up shared at a different blog each month, featuring posts from parents, teachers, homeschoolers, and students — anyone who is interested in playing around with school-level (preschool to pre-college) or recreational math.

Enjoy!

Good morning, everybody! This month’s edition of Math Teachers at Play is edition number 68. Also known as edition number {{2}^{2}}({{2}^{4}+1}). Or edition 31+37 or edition 7+61…. Alrighty, so… did you know that 68 is a happy number? That’s right, it’s not unhappy, it quite likes the way it is.

There’s certain numbers that exist that are ‘happy’ numbers. This is because the sum of the square of their digits is equal to 1. So, for 68, the two digits are 6 and 8. Adding the squares, we’re given {{6}^{2}}+{{8}^{2}}, which equates to 100. Adding the square of each of the digits makes 1, which is happy!

• Can you find some more happy numbers?
I’ll give you a hint – the first one is 1.

Anyway, back to the carnival. This carnival features 11 articles – smaller than last time, but still just as awesome and creative as ever….