One of the most amazing mathematical results of the last few years was the discovery of a surprisingly simple formula for computing digits of the number pi. Unlike previously known methods, this one allows you to calculate isolated digits - - without computing and keeping track of all the preceding numbers.
No one had previously even conjectured that such a digit-extraction algorithm for pi was possible, says Steven Finch of MathSoft, Inc., in Cambridge, Mass.
The only catch is that the formula works for hexadecimal (base 16) or binary digits but not for decimal digits. Thus, it's possible to determine that the forty billionth binary digit of pi is 1, followed by 00100100001110. . . . However, there's no way to convert these numbers into decimal form without knowing all the binary digits that come before the given string.
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Hmm....
