Mersenne Digest Wednesday, December 1 1999 Volume 01 : Number 666 ---------------------------------------------------------------------- Date: Mon, 29 Nov 1999 04:16:41 -0500 From: Larry <[EMAIL PROTECTED]> Subject: Mersenne: Nice Paper Just to let you know Stephan the last name is Murray. Although I've always loved numbers they have not always loved me. I need all the reading I can get to try and understand them. Computers are my field. That's why I find Gimps so satisfying I'm able to give something to the field of Mathematics without being a Mathematics genus. I will be hitting my 1 year anniversary with gimps on 12/10 which also happens to be my oldest daughters 21st birthday.... To date I have contributed 18.241 Years total with gimps, with a lot of time not yet reported. I am presently working on 3 ten million digit numbers one of which is 15% done. I want to thank George for putting the factoring in at the start. I found 2 ten million digit non prime numbers that I would have wasted a year on otherwise. I thought it amazing working on a number project that lasted 2-3 weeks for just one number, but now 52 week projects... come on intel where's that 25Ghz Pentium <Joke>. I could sure use one right about now. Anyway Happy Holidays everyone. Larry Murray _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Sun, 28 Nov 1999 23:29:34 -0500 From: "Vincent J. Mooney Jr." <[EMAIL PROTECTED]> Subject: Re: Mersenne: Atanasoff The Burks's book mentions Konrad Zuse and his programmable, floating-point binary Z-3, George Stibitz and the Bell Labs Model II - V; also Mark I of IBM and others. These are labeled electro-mechanical computers and the Burks say that they were well established by the mid-1930's when Atanasoff was doing his work. The Burks then go on to declare Atanasoff used the continuous electronic technology of the times; they distinguish between analog and digital mode; they declare that Atanasoff was part of chain of development with electro-mechanical computing technology first and the electronic computer technology being Atanasoff's contribution. Chapter 5 called Atanasoff Place in History covers these points and more. The Burks state that the ENIAC was not the first electronic computer. They write that it was Atanasoff who started the computer revolution. My own judgement is that Atanasoff gets 5 stars out of 5; other maybe are deserving too. I wish he were still around so I could tell him about GIMPS (Dr. Atanasoff was a PC user, not a MAC user). I also give Atanasoff 5 stars for NOT PATENTING anything. Cripes, can you image where we'd be if we had to ask permission to improve someone else's patent? At 10:11 PM 11/28/99 -0500, Jud McCranie wrote: >At 07:31 PM 11/28/99 -0500, Vincent J. Mooney Jr. wrote: > > Pleasse tell us what there is to disagree with. > >This is off-topic, but there was prior work on the Mark I, in Germany by >Zuse, and in England on the code breaking project. There is no clear >inventor of the computer in the eyes of most historians. Much of the >controversy is covered in chapter 8 of "ENIAC" by Scott McCartney and other >books such as ""Portraits in Silicon". Iowa State University seems >overzealous in promoting Atanasoff. > >+--------------------------------------------------------+ >| Jud McCranie | >| | >| 137*2^197783+1 is prime! (59,541 digits, 11/11/99) | >+--------------------------------------------------------+ > > _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Mon, 29 Nov 1999 13:23:32 -0500 From: Jud McCranie <[EMAIL PROTECTED]> Subject: Re: Mersenne: Atanasoff At 11:29 PM 11/28/99 -0500, Vincent J. Mooney Jr. wrote: > I also give Atanasoff 5 stars for NOT PATENTING anything. He (and ISU) tried to patent it. +--------------------------------------------------------+ | Jud McCranie | | | | 137*2^197783+1 is prime! (59,541 digits, 11/11/99) | +--------------------------------------------------------+ _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 30 Nov 1999 00:47:10 -0000 From: "Daniel Grace" <[EMAIL PROTECTED]> Subject: Mersenne: Has anyone seen this theorem before? Hello, I came up with the following theorem on composite Mersennes and wondering whether it was familliar to anyone and if so did they know of any interesting corollaries, relations between the terms or properties of the terms (I could not find any). If p is a prime and Mp=uv with v>1 and u=7 mod 8 then there exists integers x and w and integers n, i and j such that 2^n=x^i-(2^j)xw+w, where p=n+ij, i>1, j>1, j>n>0 and (2^j)x-1=u. Further v=1+(2^j)x+((2^j)x)^2+...+((2^j)x)^(i-1)-(2^(ij))w, or v=(((u+1)^i)-1)/u-(2^(ij))w. e.g. M11=23*89, j=3, i=3, n=2, x=2, w=1: check: u=(2^3)3-1, v=(((23+1)^3)-1)/23-2^9=89. There is always a solution where j represents the the number of lsb's before the first zero any divisor congruent to 7 mod 8 (that was my original motivation for representing the divisors in this form). Is it yet another useless theorem? What is the highest value for j that has been discovered? Thanks, - ---------------------------------------------------------- Daniel e-mail: [EMAIL PROTECTED] _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Mon, 29 Nov 1999 20:25:17 -0600 From: Ryan McGarry <[EMAIL PROTECTED]> Subject: Re: Mersenne: Atanasoff As an ISU CompSci major, we learned something about this in 101. >From what I remember, the ABC wasn't really too impressive as a computer goes. It was actually just a proof of concept, and wasn't very usable, even for checking Mersenne prime numbers. As legend has it, Atanasoff was sitting in a coffeehouse when his idea of a programmable computer with memory popped into his head. He quickly jotted the idea down in a napkin, folded it up, and saved it. Several years later, he and an engineer grad student (Berry) built the computer. He didn't document too much about the computer. When he got it to add several numbers together and implemented a stack, he called it a success and filed for the patent. ISU lost the patent application and never sent it in. They lost the rights to the patent when ENIAC was born. Atanasoff thought everything was filled out, and never bothered to double-check the patent. When he realized he hadn't received any royalties, it was too late, and ISU had torn the computer down to make room for research during WWII. In an attempt to fix things up, the CompSci dept (rightly) named their building after him. He was still very mad about losing all the patent money, and never forgave ISU for losing the paperwork. Ryan McGarry Jud McCranie wrote: > > At 11:29 PM 11/28/99 -0500, Vincent J. Mooney Jr. wrote: > > I also give Atanasoff 5 stars for NOT PATENTING anything. > > He (and ISU) tried to patent it. > > +--------------------------------------------------------+ > | Jud McCranie | > | | > | 137*2^197783+1 is prime! (59,541 digits, 11/11/99) | > +--------------------------------------------------------+ > > _________________________________________________________________ > Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm > Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Mon, 29 Nov 1999 21:46:03 -0500 From: Jud McCranie <[EMAIL PROTECTED]> Subject: Re: Mersenne: Atanasoff - --=====================_437505679==_.ALT Content-Type: text/plain; charset="us-ascii"; format=flowed At 08:25 PM 11/29/99 -0600, Ryan McGarry wrote: >As an ISU CompSci major, we learned something about this in 101. > > From what I remember, the ABC wasn't really too impressive as a computer >goes. It was actually just a proof of concept, and wasn't very usable, >even for checking Mersenne prime numbers. It was a special purpose machine that could solve a system of several linear equations. > ISU lost the patent application and never sent it in. I think that one of the books I read said that it just fell by the wayside when the US got involved in WWII, or something like that. +--------------------------------------------------------+ | Jud McCranie | | | | 137*2^197783+1 is prime! (59,541 digits, 11/11/99) | +--------------------------------------------------------+ - --=====================_437505679==_.ALT Content-Type: text/html; charset="us-ascii" <html> At 08:25 PM 11/29/99 -0600, Ryan McGarry wrote:<br> <blockquote type=cite cite>As an ISU CompSci major, we learned something about this in 101.<br> <br> From what I remember, the ABC wasn't really too impressive as a computer<br> goes. It was actually just a proof of concept, and wasn't very usable,<br> even for checking Mersenne prime numbers. </blockquote><br> It was a special purpose machine that could solve a system of several linear equations.<br> <br> > ISU lost the patent application and never sent it in.<br> <br> I think that one of the books I read said that it just fell by the wayside when the US got involved in WWII, or something like that.<br> <br> <br> <br> <div>+--------------------------------------------------------+</div> <div>| Jud McCranie |</div> <div>| |</div> <div>| 137*2^197783+1 is prime! (59,541 digits, 11/11/99) |</div> <div>+--------------------------------------------------------+</div> </html> - --=====================_437505679==_.ALT-- _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Mon, 29 Nov 1999 23:24:30 -0800 From: Luke Welsh <[EMAIL PROTECTED]> Subject: Re: Mersenne: Atanasoff Why Computers Are Computers: The SWAC and the PC by David Rutland, available on Amazon.com Pages 45-6 "...the Iowa State computer built in 1939 which was the unique creation of Dr. John Atanasoff. He is now credited with the design and construction of the first vacuum tube computer. It used a novel means for the storage of numbers, electrical capacitors." [....] "Atanasoff used 3200 small capacitors which could be charged to represent 0s and 1s of binary numbers. His arithmetic unit used vacuum tubes which made it much faster than the other computers of the time that used either mechanical wheels or telephone relays. The machine was not really a general purpose computer as it was more like Babbage's Difference Engine than the Analytical Engine. Its control circuits were wired to do one and only one important task: the solution of simultaneous algebraic equations. Although parts of the machine were built and proven, it was never put into full operation. Atanasoff didn't publish his work so it didn't make a contribution to the development of computers. In 1971 the ENIAC patent case was being litigated and the court decided that Atanasoff was the true inventor of the electronic computer because he had his idea so early. The patent that Eckert and Mauchly had on the first working electronic computer, the ENIAC, was therefore declared null and void. This ruling, of course, started up a controversy of who really invented the computer. This controversy can be resolved by giving everyone credit. Atanasoff gets the credit for the idea of a vacuum tube computer and Eckert and Mauchly get credit for going a big step further and making one that actually worked." Rutland continues to write about Konrad Zuse. His machines were true computers and he got little government help. Allied bombers destroyed his apartment and his Z3 (computer, not BMW!!). After the war he worked in Germany for IBM, designing computers. He is sometimes credited for creating the first functional computer using the stored program concept. - --Luke _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Tue, 30 Nov 1999 13:18:56 -0000 From: "Daniel Grace" <[EMAIL PROTECTED]> Subject: Mersenne: 3^m-2 and 3^n-2^(n-1) Has anyone compiled a reasonable list of exponents which produce primes for either of these functions, if so is it available on the web? Thanks, - ---------------------------------------------------------- Daniel e-mail: [EMAIL PROTECTED] _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ Date: Wed, 01 Dec 1999 14:39:32 -0600 From: Rich Harms <[EMAIL PROTECTED]> Subject: Mersenne: IPS Database Synchronization My individual account report on IPS has accumulated 18 LL tested exponents in the "Exponents Cleared since last Synchronization" section, the oldest having been completed on 29 Mar 99. In fact 5 of the oldest results recently changed status from "first LL test" to "double check". Is this a common situation across the IPS accounts, or is my account "unique" for some reason and not being cleared by the periodic synchronizations? Regards, Rich Harms _________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers ------------------------------ End of Mersenne Digest V1 #666 ******************************
