Thursday, November 8, 2012

November 8, 2012



The calendar notation said that this is day number 313 in the year 2012.   Yes, the first thing that came to mind is depicted above.  313 is Donald Duck's license plate number.

Then one observes that 313 is a simple palindrome; and the next step is to factor the number, which is a mental exercise that I have practiced for a long time:  factoring license numbers.  A quick calculation reveals that the number is prime.

There.  Fun, arithmetic lesson, and more of the you-never-know-what-you-will-get on STSTT.

Image: Disney

13 comments:

Jim said...

Prime numbers make me :-), but I forgot how to factor 15 minutes after the 9th grade.

Shelly said...

You snuck in a math lesson on me before I even realized it! Interesting~

vanilla said...

Jim, ah, Jim. The math teacher works so hard to make a lasting impression...

Shelly, gotta love an English teacher who freely uses "snuck."

Secondary Roads said...

"You-never-know-what-you-will-get on STSTT" is just one of the reasons I keep coming back. I like prime numbers. I usually adjust the volume of the TV (level is indicated numerically on the screen) to a prime number.

Vee said...

Old math teachers never die, they just ____.

vanilla said...

Chuck, mish-mash (or mich-mas), olio, potpourri. Volume at 47 works well for me.

Vee, ...cease to be a factor.

Grace said...

What I find interesting is that you know the number on Donald Duck's license plate...I was never a Disney fan. I think we all have a thing we do with numbers - I do dates - (not the kind you eat tho I do like them)...

Shelly said...

Snuck is sneaking its way back into formal usage, according to the rulers of grammardom. And it's just fun to say~

vanilla said...

Grace, my head is full of useless information.

Shelly, I am well aware that the grammar police have relaxed their grip on the language in many ways. I know that the verb form under discussion is now allowed; but it has not yet sneaked into my personal usage.

Sharkbytes said...

Hmmm- I never knew the duck's license number. So you just sidetracked me into playing with numbers. The first 16 sets of twin primes are separated by 3,6,6,12,12,18,12,30,6,30,12,30,12,6,30

That's really weird. All divisible by 3. There's something going on there. I'm sure someone has already figured it out.

vanilla said...

Shark, numbers are fascinating. Did you note as well that except for the first pair of twin primes, the number centered between each pair of twin primes is always divisible by six? So then your separation is also divisible by six. Mathematicians are weird.

Sharkbytes said...

Suddenly prime numbers don't seem so random any more. But has someone figured out the sequence of the progression? Is there one. Sorry, I don't feel motivated enough to spend two days trying to figure it out and then have to give up in the end. I'm pretty good at spotting progressions, and got As through Calc III and Analytic Geometry, but that was X years ago, and this looks like a nasty problem.

vanilla said...

Shark, I think there remain sufficient mysteries about prime numbers to occupy mathematicians more dedicated than I for a long time to come.