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I recently used Bailey–Borwein–Plouffe formula to implement a π digit generator. Now I also want to implement an e digit generator, for the Euler number.

I've been searching and reading papers but it looks like there is no BBP formula for e. Is there one? Does anyone know if there has been recent progress on this?

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I wish I had 50+ reputation so I could comment : I visited your website and I saw that you are not actually using what the BBP is famous for namely extracting the $n$-th digit in base-16. Instead you are giving all the digits in base 10. If that is what you want for $e$ then the power series $\sum_{k \geq 0} 1/k!$ already does the job sufficiently well.

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  • $\begingroup$ Now I have 50+ reputation! No need to up-vote anymore. $\endgroup$
    – COnstructor
    Commented Jan 8, 2017 at 5:36
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What you are actually looking for, is the Spigot Algorithm which is also known as "droplet algorithm".
That algorithm has been described a few years ago in the german "Spektrum der Wissenschaft" and should thus also have been described in the "Scientific American".

Especially the algorithm for $e$ is known and an implementation in R can be found here.

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