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Today is Pi Day.


SIEGEL: Not that kind of pie. Pi - the Greek letter P - which represents the ratio of the circumference of a circle to its diameter. Evidently, it's the fact that the Greek words for circumference - which gave us the words periphery and perimeter, start with pi - that accounts for its usage.

Well, today is Pi Day.


SIEGEL: Still not that kind of pie. It's Pi Day because it is March 14th - 3-14. And pi equals 3.14, and it goes on, 159 - it just keeps on going because pi is, of course, the world's most famous irrational number, and it is an undying source of interest to many highly rational people.

For example, Mark Umile of Upper Darby, Pennsylvania, who is the North American record holder for memorizing the digits of pi. Welcome to the program, Mark Umile.

M: Thank you.

SIEGEL: And first of all, how far did you get with your memorization?

M: With memorization, I was attempting on reaching 13,000, when I was achieving the record, but made the error at the 12,888th place. So right in the back of that, I have 12,887 digits memorized.

SIEGEL: And do you remember which digit you got wrong?

M: That's the record. Yes. Yes, I do. In fact, it was a four.

SIEGEL: What led you to do this, to memorize pi?

M: I have always been fascinated in the human memory. And for anybody who wants to know how good their memory is, pi is the ultimate test to finding that out. And that it was also a mystical experience, in the fact that the digits of pi have no rhyme or reason. They have no patterns whatsoever. But they are consistent - been written in stone in their places where they belong. It's just knowing what number comes next.

SIEGEL: Well, perhaps you'll inspire someone listening to attempt this as well. What was your method? How did you go about memorizing all those digits of pi?

M: Well, I used to work in an opera house in the Philadelphia area. I had always been interested in classical music and looking at notes, musical notes on a manuscript, on a page. And each one of them, as you know, with music comes in beats and rhythms. And I figured why not apply that to the digits? So, I undertook to separate the digits in clusters of two, clusters of four and up to clusters of six.

SIEGEL: I would tape-record my voice onto an audio cassette recorder, and putting emphasis on certain numbers, changing the tone of my voice, sort of in a singsong, dancelike type of rhythm and constantly listening again, and again and again.

SIEGEL: There are some children in some traditions who are raised to be able to memorize and recite the entire Koran or the entire Torah. Were you - did you have any similar, any training like that of intensive memorization as a little kid?

M: No, no, I did not. I was, as far as literature is concerned, I was always involved in acting, in theater. That's memorizing lines in a script. So, I guess, possibly that could count.

SIEGEL: Well, Mark Umile, thank you very much for talking with us about your achievement as North American record holder.

M: Oh, thank you very much. Yup.

SIEGEL: And we don't have enough time for even a hundred digits of pi, but I was wondering if, before you left, you could at least give us a couple of dozen.

M: 3.141592653589793238462643383279502884197...

SIEGEL: Actually, this about six dozen digits. And to hear Mark Umile do 41 dozen digits of pi - it'll take about 100 seconds - you can go to our Web site,

M: ...7982148086513282306647093844609550582231725...

SIEGEL: And happy Pi Day from ALL THINGS CONSIDERED at NPR News.

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