Where does the sequence 123456789 first occur in the decimal expansion of pi?

Answer 1

Too bad it isn't in the first 200,000,000 digits, but you have a nine-digit string (a billion combinations). There was only about a 1 in 6 chance of finding it in the first 200 million.

I did find 12345678. Close, but no cigar.

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Note to Michael, below: Actually, if you assume pi is normal (not proven, but probably true), this is a nice application of Poisson distribution. If your string is n digits long, then there are 10^n total combinations. Using Poisson, the probability of finding the string in the first d digits of the decimal expansion is 1 - 1/(e^f), where f = d/10^n and e = 2.71828...

Answer 2

I can push out the limit to 500,000,000. Incidentally, just because pi has an infinte number of digits and does not repeat, does *not* mean that 123456789 must be in there somewhere. It only means that it *might* be in there. Quite a bit of research is going on about how to even properly formulate this intuitive guess that 123456789 should be in there somewhere.

An interesting question is whether even a probability can be worked out as to whether any particular sequence is in pi.

Answer 3

It does not occur in the first 200,000,000 digits of pi. I'm not sure if it does occur.

Answer 4

It doesn't appear in the first 200,000,000 digits, but it would have to appear somewhere since pie has an infinite number of digits! I JUST FOUND IT!!!!! It appears at the 523,551,502nd digit.

Answer 5

As one person claims to have found it, the question for you now is whether or not you can trust that answer.