## Rockmore: Elevenses

#### 11/10/11 7:55AM By Dan Rockmore

(Host) Ever give much thought to the number eleven? Well, according to
mathematician and commentator Dan Rockmore, tomorrow would be a good day
for it.

(Rockmore) No, when you wake up tomorrow, your digital alarm clock won't be lying and you won't be seeing double... or triple... because tomorrow really will be eleven-eleven-eleven. That's right, it's the eleventh day of the eleventh month of the eleventh year of this century! So, let's take a moment to celebrate the number known at craps tables around the world as "the natural."

First off, eleven does have some nice mathematical characteristics. It's a prime number, meaning that it can only be divided evenly by itself and one. That already makes eleven something of a rare bird and worth some recognition. A more interesting fact is that if you can find a number divisible by 11 - and you then reverse the digits in that number - the reversed number is also divisible by eleven. So for example, 132 is 11 times 13 and when reversed as 231 we get a number that is 11 times 21.

But the truth is, dear old eleven is largely overshadowed by those first ten numbers. Who ever heard of a Top-eleven list? Countdowns start at ten. Poor eleven, always the odd number out!

Eleven's outsider nature is reinforced by its name. Who hasn't noticed that after we get through the numbers one to nine, most of the numbers have names that give a pretty good indication of what they stand for: thirteen - three and ten, twenty-seven - seven and twenty, two hundred - well, two hundreds... anyway, you get the picture - or the number as it were - but where's the clue in eleven? E-leven - sounds to me like an internet bread bakery! Why don't we say something like: ten, one-teen, two-teen, thirteen...?

Well, in fact, there's a pretty interesting story in the name eleven. It comes from the German word "einlif" meaning "one left," or what 's left over after you've tried to count to eleven using your fingers. That's right, eleven is the number that sends us to our feet. The same is true for twelve, derived from the word for "two left," meaning two left over, and which despite its further suggestion of looking to your toes, has nothing do with two left feet.

So the outcast eleven reminds us that the decimal system we use for the everyday representation of numbers, based on writing numbers as collections of powers of ten most likely comes from the simple fact that those earliest of Germanic accountants used their hands as computers, communicating something like the number of sheep in the flock by using their fingers, a notion later memorialized in the use of the word "digit" for each of the places in a number.

My own earliest memories of eleven are decidedly non-mathematical. I can still recall puzzling over the mysterious word "Elevenses" that I only later learned meant the morning snack of bread and honey for dear old Winnie the Pooh and Paddington Bear.

Hmm. Maybe that E-leven bakery isn't such a bad idea after all.

(Rockmore) No, when you wake up tomorrow, your digital alarm clock won't be lying and you won't be seeing double... or triple... because tomorrow really will be eleven-eleven-eleven. That's right, it's the eleventh day of the eleventh month of the eleventh year of this century! So, let's take a moment to celebrate the number known at craps tables around the world as "the natural."

First off, eleven does have some nice mathematical characteristics. It's a prime number, meaning that it can only be divided evenly by itself and one. That already makes eleven something of a rare bird and worth some recognition. A more interesting fact is that if you can find a number divisible by 11 - and you then reverse the digits in that number - the reversed number is also divisible by eleven. So for example, 132 is 11 times 13 and when reversed as 231 we get a number that is 11 times 21.

But the truth is, dear old eleven is largely overshadowed by those first ten numbers. Who ever heard of a Top-eleven list? Countdowns start at ten. Poor eleven, always the odd number out!

Eleven's outsider nature is reinforced by its name. Who hasn't noticed that after we get through the numbers one to nine, most of the numbers have names that give a pretty good indication of what they stand for: thirteen - three and ten, twenty-seven - seven and twenty, two hundred - well, two hundreds... anyway, you get the picture - or the number as it were - but where's the clue in eleven? E-leven - sounds to me like an internet bread bakery! Why don't we say something like: ten, one-teen, two-teen, thirteen...?

Well, in fact, there's a pretty interesting story in the name eleven. It comes from the German word "einlif" meaning "one left," or what 's left over after you've tried to count to eleven using your fingers. That's right, eleven is the number that sends us to our feet. The same is true for twelve, derived from the word for "two left," meaning two left over, and which despite its further suggestion of looking to your toes, has nothing do with two left feet.

So the outcast eleven reminds us that the decimal system we use for the everyday representation of numbers, based on writing numbers as collections of powers of ten most likely comes from the simple fact that those earliest of Germanic accountants used their hands as computers, communicating something like the number of sheep in the flock by using their fingers, a notion later memorialized in the use of the word "digit" for each of the places in a number.

My own earliest memories of eleven are decidedly non-mathematical. I can still recall puzzling over the mysterious word "Elevenses" that I only later learned meant the morning snack of bread and honey for dear old Winnie the Pooh and Paddington Bear.

Hmm. Maybe that E-leven bakery isn't such a bad idea after all.