Digits of Pi

A Hamburg mathematics professor, Hermann Schubert, once said (in 1889):

"Conceive a sphere constructed with Earth at its center, and inagine its surface to pass through Sirius, which is 8.8 light-years distant.

Then imagine this enormous sphere to be so packed with microbes that in every cubic millimeter millions upon millions of these diminutive animalcula are present.

Now conceive these microbes to be unpacked and so distributed singly along a straight line that every two microbes are as far idstant from each other as Sirius is from us, say 8.8 light years.

Conceive the long line thus fixed by all the microbes as the diameter of a circle, and imagine its circumference to be calculated by multiplying its diameter by pi to 100 decimal places.

Then, in the case of a circle of this enormous magnitude even, the circumference so calculated would not vary from the real circumference by a millionth part of a millimeter.

This example will suffice to show that the calculation of pi to 100 or 500 decimal places is wholly useless."

I got this quote out of Petr Beckmann's excellent book, A History of pi.

pi goes on and on and on
and e is likewise cursed.
I wonder which is larger
When the digits are reversed

(not original with me; I'll try to find the source.)

Zap a barn; c dames, elephants, Fo, gelded horse, imp, jacks,
kangaroo, limberous mammals nervously owe PI QED; readying some tested,
um, veiled word, xap you! Zygotes are by catback dismissed,
evils _ go hogsback injuring John; K leapingly mounted N

Any additions? You won't believe how long this takes until you try it!

The first million digits of pi were calculated in 1973 using a CDC 7600. The calculation took 23 hours, and was produced using a fairly common arctangent series.

The problem with the arctangent algorithm, however, was that it had an unsuitably high growth rate, on the order of n-squared -- in other words, computing twice as many digits of pi as you had so far would take four times as long. In 1976 Eugene Salamin rediscovered a formula used by Gauss which was more computation-intensive, but had a much slower growth rate.

Using this new formula with the increasingly-available supercomputers, the first million digits of pi was a snap. Pi was expanded to 2 million digits in 1981, 16 million digits in 1982, and the first billion digits of pi were computed and verified in 1989.