Finding book ISBN numbers in Pi


It would be more interesting to find entire books in PI. As any series of characters can be converted to numerical form, it wouldn’t be impossible for some stretch in PI to happen to be that number.

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Apophenia for geeks :slight_smile:

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How about getting the MD5 hash of a book and finding that in Pi?

Then depending on the data interpretation convention used, stretches of pi are already copyright infringements.

I think pi came before all those books.

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Does that mean all copyright is bunk because every book/recording ever already existed in nature? :smile:

This isn’t a rip of a DVD, it’s just a file containing a segment of Pi.


I am instantly reminded of the ending of “Contact” (the book).

(No spoiler here, go read the book!)

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My friend used to joke he wanted to take a text, interpret it as a number and add a decimal place to the left, then encode the entire text by making a notch a fraction of the way down a stick where the fraction was the number with the leading decimal.

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Sure, that’s true, but to prove it in a court of law you might have to calculate pi to a rather large number of digits.

Your friend is probably great fun at parties.

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Man, Licentiate seminar on environmental engineering and biotechnology is always the first.

If you like this post…


Innocent until proven guilty.

They’d have to calculate all the digits to prove it wasn’t there.


It’s interesting to ponder that somewhere within the value of PI is the numerological description of an entire alternate universe, described particle-by-particle, where the laws of physics are such that the value of PI is exactly 3, as is taught in the Bible.

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I wonder what the longest sequence of integers found at least twice in pi is, so far.

Clearly the universe was made on purpose, by the U.S. ISBN Agency.


Also, at some stage (or at an infinite number of stages), the entire sequence of pi up to that point will be repeated.

Is this actually true? It feels true but I suspect there’s some weird set theory catch.

Edit: Are the digits of Pi considered truly “random?” They’re certainly not arbitrary.


Man, that was a good episode of Mathnet…