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|    sci.math.symbolic    |    Symbolic algebra discussion    |    10,432 messages    |
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|    Message 9,230 of 10,432    |
|    astojifrank@gmail.com to Simon Plouffe    |
|    Re: The story behind a formula for Pi (1    |
|    04 Jan 17 15:03:57    |
      On Monday, June 23, 2003 at 10:14:32 PM UTC-8, Simon Plouffe wrote:       > This note explains the story of the so-called Bailey-Borwein-Plouffe       > algorithm       > and formula.       >        >        > The story began many years ago in 1974 when I wanted to find       > a formula for the n'th digit of Pi. I was studying rational and       > irrational       > numbers. With my calculator I was computing inverses of primes and       > could       > easily find a way to compute those inverses in base 10 to many digits       > using       > congruences and rapid exponentiation. Since it appeared impossible to       > do       > the same for Pi, I wanted then to find a simple formula f(n) that       > could compute       > the n'th digit of Pi. I had that idea for 20 years.       >        > Since the computation of Pi looks       > more complicated than the number E , i.e. exp(1), I studied a way to       > compute       > that number instead. At that time (around 1983), I had a simple Basic       > program       > that used a spigot algorithm to compute E, as expected that algorithm       > worked but       > of course but was taking an increasing amount of memory. My question       > was :       > why can't we do it for E or Pi or any irrational numbers like sqrt(2).       >        > It was during the year 1994 that I began to compute arctan series but       > I did not       > realized that this meant a lot. I was able to use an algorithm to       > compute arctan       > of 1/5 with fast exponentiation without realizing that it could       > compute arctan(1/5)       > in base 5 very fast since the rapid exponentiation was natural in that       > base.       >        > Later in 1995, around august 7 of that year I suddenly realized that       > log(2) was       > fast computable in base 2. Since I had a bit of experience with spigot       > algorithms       > and also my little Basic program to compute arctan, it was not       > difficult to adapt       > the algorithm to log(2).       > In the next few days I made my first program : A program to compute       > log(9/10)       > in base 10 using a very small amount of memory and very fast. The       > program had       > 432 characters long.       >        > That discovery was a shock to me. I realized that I had found it yes       > but it was not       > new to me since I could do arctan(1/5) easily too but it took me 2       > years to realize it.       >        > This is where I began to use Pari-Gp, that program could find an       > integer relation       > among real numbers (up to a certain precision), very fast.       >        > During my stay at Bordeaux University in 1992-1993 I perfected that       > program I had       > that could interface Pari-Gp and Maple. That little Unix script had an       > enormous       > advantage of flexibility because I could set up a series of real       > numbers to test among 1       > unknown. At that time I was beginning to find new results, the       > programs were able to       > find identities.       >        > That program was the one that found the formula for Pi in hexadecimal       > (or binary).       > I also used another one : PSLQ. It was a good program but a bit       > cumbursome to use       > since it is written in fortran. Nevertheless I made an interface to       > Maple too.       > Pari-Gp was by far easier to use and faster for small cases (up to 10       > real numbers at       > the time with 100 digits precision was enough for those kind of       > problems).       >        >        >        > This is where I made the biggest mistake in my life : To accept the       > collaboration       > of Peter Borwein and David H. Bailey as co-founders of that algorithm       > and formula       > when they have found nothing at all. David Bailey was not even close       > to me when       > I found the formula. He was added to the group 2 months after the       > discovery.       >        > I was naively thinking that I could negociate a job as professor at       > Simon Fraser       > University, which failed. I am very poor at negociations.       > I remember that day when the Globe & Mail newspaper article went out       > in October       > 1995. I was at Jon borwein's house and he had a copy of the newspaper       > in hand.       > This is where I asked him to become a professor at SFU. He simply       > replied right       > away < don't even think about it >. I thought, this is the best chance       > I will ever have       > to become a professor there, since it failed, I decided that I had to       > leave that place.       >        > I was very frustrated at that time, in late 1995 after the discovery.       > I realized that       > many small details where terribly wrong. They were getting a lot of       > credit for the       > discovery and I had the impression of not getting anything in return.       > My strategy       > failed. One of those details was the article of the Globe and Mail, I       > asked Peter Borwein       > : why did they putted the photo of you and your brother on the article       > ? Your brother       > has nothing to do with this!. He simply replied that the Public       > Relations at the       > University made a mistake.       > Later that year, I was invited to a ceremony in Vancouver for the CUFA       > (faculty of       > the year Award).       > This is a prize with plaque and mention that those 2 brothers received       > for the       > discovery of the formula. They simply mentioned my name at the       > ceremony and       > I received nothing at all. They made a toast to the queen of England,       > I did not       > stand up.       >        > In late 1995, there was that Canadian Math Soc. congress in Vancouver,       > I was not       > invited to talk about the discovery. There was even a guy (Stan Wagon)       > that said       > to me, I don't know if you have anything to do with this but in all       > case, this is       > good for you isn't ?       >        > Then in 1996, I realized that if I get up at night to hate them it is       > a very bad sign,       > it means that I have to leave that place (Simon Fraser university).       > I was convinced I had no future at all with those 2 guys around.       > I was making serious plans to leave.       >        > The story of the formula (my formula), was not the only one. The same       > thing happened       > with the ISC (the Inverse Symbolic Calculator). The story is even more       > ridiculous.       > I opened the site with my constants in July 1995 and it was an       > immediate success.       > The 2 Borweins had nothing to do with that thing, I had made the       > tables and all       > of the Unix programs to run it. The precious help I had was from Adam       > Van Tuyl, a       > graduate student, he made most of the code behind the web pages, later       > Paul Irvine       > made some additional code.       >        > At that time the local administrator of the lab. tried to convince me       > to stay even to pay me       > for maintaining the ISC, I refused. I wanted to leave with what I had       > : my tables of       > real numbers and sequences I worked for years (since 1986). This is       > why I opened the       > Plouffe Inverter with my name in 1998, to keep what was mine.              [continued in next message]              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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