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**Leroy****Guest**

I've heard that there is a function that gives nth digit of pi,is it true?if it is i'd like to know more about it.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,341

Hi;

Yes, it is called a spigot algorithm. It can zero in on the nth digit without having to get all the preceding ones

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**Leroy****Guest**

Could you please tell me more about it

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,341

Hi;

Here is an example of a spigot algorithm being used to get the 50 th digit from ln(2). Process is the same for pi.

http://www.mathisfunforum.com/viewtopic … 19#p229919

To see how pi is done check out the BBP formula right here.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**Leroy****Guest**

Thanks

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,341

Hi;

Your welcome.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,000

Hi bobbym

Is there a way of getting the nth decimal digit of pi by a spigot algorithm?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,341

Hi;

None that I know of, the BBP is for hexadecimal digits.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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