# Mathematics Carnival 51

By Murray Bourne, 24 Apr 2009

Welcome to the 51st Carnival of Mathematics.

After a not-so-short hiatus (6 weeks ofnugg deadly silence), I'm happy to present **Math Carnival #51**, aka "The Resurrection Carnival".

Random bits of trivia about 51 throughout history:

- The year 51 (AD, or CE) in the Julian calendar shared one thing in common with today's Carnival — it's start date was a Friday.
- In the Gregorian calendar, 1751 also started on a Friday.
- Euler published his theory of logarithms of complex numbers in 1751.
- There is no truth to the rumor that this carnival disappeared for some time because the coordinator, Alon Levy, got lost in Area 51.

On with the show.

## Human bodies

**John Cook** inspires us to consider some math behind elephants and mice in Metabolism and power laws. When not blogging, John works in a cancer clinic.

Blog home: The Endeavour.

## Calculus

In Aspects Of A Topic, **Vlorbik on Math Ed** argues the case for considering the formula for the length of a curve parametrically, rather than the normal asymmetric definition .

Blog home: Community College Calculus.

## Beginnings and Endings

Benford's Law — One is NOT the Loneliest Number has **Pat Ballew** pointing out that the first cardinal number is surprisingly common when describing quantities.

Blog home: Pat'sBlog.

Inspired by Benford's Law and Pat's article, I did a quick google to see how many search results appeared for various numbers, and came up with:

1: 21,580,000,000

2: 19,990,000,000

3: 15,990,000,000

4: 12,780,000,000

Indeed, the number of results decreases until 9, but there is an upset for 10:

9: 8,200,000,000

10: 12,840,000,000

And at the other end of the number line, **Barry Leiba** in Infinity plus one discusses large numbers of hotel guests.

Blog home: Staring At Empty Pages.

## Massively Collaborative Mathematics

**Jason Dyer** gives a "simple as possible" overview of Timothy Gowers' initiatives in A gentle introduction to the Polymath project. The post gives the background to the density Hales-Jewett problem. The line that caught my eye was from Gowers: "Is massively collaborative mathematics possible?".

Blog home: The Number Warrior.

## Ball Stacking

An interesting coincidence occurred with the following 2 posts. Both talk about stacking spheres in square pyramids, but in quite different contexts.

**TwoPi** offers us Pascal’s Pyramid (part 1 of 3), where he ponders the nature of a three dimensional analogue of the Pascal Triangle.

Blog home: 360.

**Mike Croucher** challenges the reader to find the volume of a square pyramid that completely surrounds a stack of cannon balls in Problem of the week #6 - Cannonballs.

Blog home: Walking Randomly.

## Amicable Numbers

In an unusual post, **Paul Dyson** shows us what would happen when The Numbers go Social Networking. The links point to nice summaries of the different number types.

## Free Math Downloads

My contribution to this Math Carnival is the post Free math software downloads, which may come in handy in these tight economic times.

## Future of the Math Carnival

I'm not sure where the Carnival goes from here. There seems to have been a slide in interest in recent months.

**My proposal:** Why not draw up a schedule so that we host once every (say) 4 months? Would that work, do you think?

That concludes this edition. Goodnight and good luck.

See the 12 Comments below.