Two Interesting BigNum Stories (Via Slashdot)


Surprised these weren't posted earlier, as they came via Slashdot yesterday.

1. HP Patents BigNum Implementation

This one concerns a patent issued to HP, and specifically Cyrille de Brebisson. Apparently, there may be prior art which would invalidate the patent - specifically, in Knuth's "Semi-Numerical Algorithms" as well as other papers stretching back to 1912.

The Slashdot story is at and the patent itself is viewable at

2. Pi to 2.7 Trillion (Approx) Decimal Digits

Now that's a BigNum! Slashdot discussion is at while Fabrice Bellard's page on how he did it is at


--- Les



Thanks! Interesting pi story. I liked how a guy with his home computer decided (and managed) to do this.


Pi to 2.7 Trillion (Approx) Decimal Digits

And the winner is...


(OS speaking, of course it is also an excellent human performance)

Very good news, thank you.


There are quite a few songs written about pi, here is a favorite.

Getting more OT, musician John Boswell's Symphony of Science uses Auto-Tune software to create songs from the spoken words of Carl Sagan, Stephen Hawking and others. With the idea of promoting science, all songs are free to download.



darn it, you guys saw that...

I obviously did not know about the prior art when I filed the application...

what is the stangest is that the thing got accepted!

one of the PB is that HP is telling us NOT to look for prior art and NOT to look in publications to see other's inventions/idea. the reason for this is that in court, when comes time to defend a patent, if the other party can show that you had knowledge of their stuff, it can be damaging to you....

anyhow, I have now made /. twice, once for good (developer friendly 20b) and once for bad (stupid patent)...


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