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The First 50M Prime Numbers (1975) [pdf]

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Re: The First 50M Prime Numbers (1975) [pdf]

#21

I like how the feeling of the author's excitement about the topic is embedded in the text """ upon looking at these numbers one has the feeling of being in the presence of one of the inexplicable secrets of creation. """ """ I hope that with this and the other pictures I have shown, I have communicated a certain impression of the immense beauty of the prime numbers and of the endless surprises which they have in stor…

And I love how he didn't really assume any prior knowledge for the reader. It was very accessibly written.

Re: The First 50M Prime Numbers (1975) [pdf]

#22

It's simply amazing what people did with the limited computing they had available to them at the time. Even when it was available, you only got an allotment of it and had to figure out how to do everything you wanted within that allotment. Here we are with many orders of magnitude of computing power that we have to ourselves, 24/7, and mostly we're using all that power to browse the Internet :P Calculating the first…

The IBM mainframe I had access to in the 80s at University of Illinois of Chicago had quotas of compute time (that reset on a weekly basis). Since I worked in the computer center, I had an account that had a larger quota (or possibly unlimited, I don’t remember now, perhaps the unlimited was when I advanced to a staff level?). One of the more entertaining things was when one class started having people code in Ada. Unfortunately, the Ada compiler was a CPU hog and a single compilation was enough to use up a week’s quota. As a result, students had to work in teams and share access to their online disks (VM/CMS did allow different modes that allowed privacy for things like email to be kept even while allowing read access to the rest of the stuff on the disk—also noteworthy was the lack of subdirectories). The team members had to switch to a different account after each day‘s work since they would exhaust each account’s quota. If you inadvertently logged out too soon, it was possible that a homework assignment could not be completed.

Re: The First 50M Prime Numbers (1975) [pdf]

#23
post #9

Earlier quoted context omitted.

That's a very cool accomplishment. What language did you use to write the code? I also have another question, did you witness the transition from punched cards to terminals?

This would have been assembly code, probably 6809 or 68000 system I had back then. 6809 would have required dumping intermediate data to a disk. I don't recall just when I first got a hard-disk, which would probably have been a massive 10 megabytes in size. And yes, I saw that transition. I learned to program using Fortran IV and IBM 11/30 assembly in the mid-70s, using punched cards. Wrote a MIXAL assembler and simu…

You just reminded me of when I bought my first PC in 1990 and one of my former professors, on learning I had bought it with a 200MB hard drive declared that I was crazy to buy such a large hard drive because I would never fill it up.¹

1. Reader, I filled it up.

Re: The First 50M Prime Numbers (1975) [pdf]

#24
post #18
post #5

[flagged]

You can produce such a PDF at home these days fairly easily.

But if you want to go really hard core, the thing to do is to build a mechanical Babbage-style machine that will calculate those 50,000,000 primes and print them letterpress.

Re: The First 50M Prime Numbers (1975) [pdf]

#25
post #23
post #9

Earlier quoted context omitted.

This would have been assembly code, probably 6809 or 68000 system I had back then. 6809 would have required dumping intermediate data to a disk. I don't recall just when I first got a hard-disk, which would probably have been a massive 10 megabytes in size. And yes, I saw that transition. I learned to program using Fortran IV and IBM 11/30 assembly in the mid-70s, using punched cards. Wrote a MIXAL assembler and simu…

You just reminded me of when I bought my first PC in 1990 and one of my former professors, on learning I had bought it with a 200MB hard drive declared that I was crazy to buy such a large hard drive because I would never fill it up.¹ ⸻ 1. Reader, I filled it up.

One of my more embarrassing memories (technical ones, anyway) was having an argument with a couple of friends in college in 1988/89. I felt that sure, an internal hard drive is a nice feature, but swapping floppies wasn't all that terrible.

You could have made a significant amount of money betting against my technical predictions over the last few decades.

Re: The First 50M Prime Numbers (1975) [pdf]

#26

I like how the feeling of the author's excitement about the topic is embedded in the text """ upon looking at these numbers one has the feeling of being in the presence of one of the inexplicable secrets of creation. """ """ I hope that with this and the other pictures I have shown, I have communicated a certain impression of the immense beauty of the prime numbers and of the endless surprises which they have in stor…

[deleted]

Re: The First 50M Prime Numbers (1975) [pdf]

#27
post #24
post #18

Earlier quoted context omitted.

You can produce such a PDF at home these days fairly easily.

But if you want to go really hard core, the thing to do is to build a mechanical Babbage-style machine that will calculate those 50,000,000 primes and print them letterpress.

Well, you could build a pdf that does the calculation.

(PDF is actually an executable format and allows computation inside of it.)

Re: The First 50M Prime Numbers (1975) [pdf]

#28
Pedantic correction:

"You certainly all know what a prime number is: it is a natural number bigger than 1 which is divisible by no other natural number except for 1."

By that definition, the set of prime numbers is an empty set. (All natural numbers greater than 1 are divisible by at least two other numbers: 1 and itself).

Re: The First 50M Prime Numbers (1975) [pdf]

#29

It's simply amazing what people did with the limited computing they had available to them at the time. Even when it was available, you only got an allotment of it and had to figure out how to do everything you wanted within that allotment. Here we are with many orders of magnitude of computing power that we have to ourselves, 24/7, and mostly we're using all that power to browse the Internet :P Calculating the first…

> Even when it was available, you only got an allotment of it and had to figure out how to do everything you wanted within that allotment.

IIRC computing primes was a popular way to test hardware; it’s fairly easy to compare results between machines, and both having a faster CPU, more CPUs and having more memory (simple example: if you do trial division, you can keep a larger table of ‘small’ primes around to quickly weed out most integers)) will speed up computations.

It then sort-of became a marketing goal to beat your competitors, so cleverer and cleverer algorithms were developed.

Because of that, those records had less trouble with resource allotments.

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