## Nine More Kinds of Pi: Happy Pi Day 2015!

Since this blog takes its name from an artist who wrote about pie and painted π (see last year’s post), I try to offer a little tribute to this beloved irrational number each Pi Day. Today, at 9:26:53 am and pm (twice!), the date will spell out the first ten digits of the number. Well, it will if you write the date in the American style: 3/14/15, 9:26:53.

Last year, I managed to offer nine kinds of π / pie. And this year,… here’s another nine!

**1. Andrew Huang’s “Pi Mnemonic Song” (2013)**

I’ve featured π music on this blog before (see here and here), but only just discovered this piece, thanks to Paul DeGeorge, who shared it on Facebook. Yes, there’s a minor glitch late in the video. As Huang acknowledges on the song’s YouTube page, “there was an editing error at 1:18 with a couple of the numbers, but the song does all truly line up with Pi.”

**2. “Joy of Bubbles,” π art from Cristian Vasile (2014)**

Vasile describes the piece as the “First few thousands digits of pi displayed over radial paths. Small size dots.” In an article from last year’s Pi Day, the *Guardian* shares art from Vasile and others.

**3. π in superballs (2015)**

Yes, these are my superballs, on my bathroom floor. Why do you ask? Also, technically, they’re not superballs (a brand name) — they’re just bouncy rubber balls. But they do spell π out to the 11th digit.

**4. Sandra Boynton’s Pig & Pi (2015)**

Every day, Boynton posts something funny via Facebook and Twitter — here’s what she has for today. (I hope the pig finds some *pie* soon….)

**5. Stephen Doyle’s global Pi (2015)**

Doyle’s photographic portrait cleverly places the number within a circle, half of a globe — presumably to signal global Pi Day. This piece of art accompanied Manil Suri’s “Don’t Expect Math to Make Sense” in the *New York Times*, 14 Mar. 2015.

**6. Technische Universität Berlin’s Pi mosaic**

Located outside the Maths Department at the Technical University of Berlin.

**7. Tim Habersack’s π in color** (click for larger image)

Click on the above to see the larger image (it takes Pi out to 786,432 digits). As Habersack explains, he “Wrote a php script which reads in the characters of pi one at a time. I assigned a single color to each character, 0 = white, 1 = teal, 2 = blue, etc. I create an image, and starting at position 0,0, I draw in my pi calculation one pixel at a time.”

**8. Michael Albert’s Pi collage**

From PBS’s “6 Ways to Celebrate Pi Day.”

**9. The Barbury Castle Crop Circle (allegedly)**

Located in Wiltshire, England, this crop circle is alleged to be a graphic representation of the first ten digits of Pi. Full explanation here, though I’m a bit skeptical of it, myself. Whether or not it spells out Pi, it is an impressive crop circle.