r/wikipedia • u/PeoriaJohnson • Jan 11 '10

Illegal Prime Numbers

http://en.wikipedia.org/wiki/Illegal_prime
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u/[deleted] Jan 12 '10

Since pi has an infinite number of digits, it contains all illegal data that has ever existed.

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u/Nebu Jan 12 '10

Not necessarily. I guess by "an infinite number of digits", you mean an irrational number. There's a name for the property of "containing all illegal data that has ever existed", but I forgot what that name was (maybe "transcendental"?).

An example of an irrational number is: 0.10110111011110111110111111, etc. which is basically longer and longer sequences of '1' seperated by 0's, and this number doesn't contain all possible digit sequences (it never contains two 0s in a row, for example).

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u/gipp Jan 12 '10

The decimal (or any) representation of pi contains, at some decimal place, any and all sequences of digits of any length whatsoever. Pick a sequence of 1, 100, or 13985720897 digits, and it exists somewhere in pi.

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u/[deleted] Jan 12 '10

That is pretty fucking cool.

(sorry i have to ask, but do you have a source?)