# calculating pi

**URL:** <https://boards.straightdope.com/t/calculating-pi/2960>\
**Category:** Factual Questions\
**Created:** [September 1, 1999, 6:50pm UTC](https://boards.straightdope.com/t/calculating-pi/2960 "1999-09-01T18:50:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![mikan](https://avatars.discourse-cdn.com/v4/letter/m/cc9497/32.png) [@mikan](https://boards.straightdope.com/u/mikan)\
**Post date:** [September 1, 1999, 6:50pm UTC](https://boards.straightdope.com/t/calculating-pi/2960/1 "1999-09-01T18:50:00Z")

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What’s the mathematical procedure involved in calculating pi. Say you’ve got pi worked out to the first 100 digits; how, then, do you figure out the 101st?  
(Yes, I know computers have been used to calculate pi far beyond the first 100 digits, but that’s precisely my question: what is it, exactly, that a computer is “doing” here to calculate each subsequent significant digit?)

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**Author:** ![Alphagene](https://avatars.discourse-cdn.com/v4/letter/a/8e7dd6/32.png) [@Alphagene](https://boards.straightdope.com/u/Alphagene)\
**Post date:** [September 1, 1999, 6:59pm UTC](https://boards.straightdope.com/t/calculating-pi/2960/2 "1999-09-01T18:59:00Z")

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[http://www.straightdope.com/classics/a3\_357.html](http://www.straightdope.com/classics/a3_357.html)