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Prime numbers so memorable that people hunt for them

scientificamerican.com

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Re: Prime numbers so memorable that people hunt for them

#31

Post by TeMPOraL »

lehi wrote: post #3

https://en.wikipedia.org/wiki/Belphegor%27s_prime "666" with 13 0's on either side and 1's on the ends.

> Belphegor (or Baal Peor, Hebrew: בַּעַל-פְּעוֹר baʿal-pəʿōr – “Lord of the Gap”) is, in the Abrahamic religions, a demon associated with one of the seven deadly sins. According to religious tradition, he helps people make discoveries. He seduces people by proposing incredible inventions that will make them rich.

Huh. Would feel right at home in our industry.

> According to some demonologists from the 17th century, his powers are strongest in April.

Any demo days or other significant VC stuff happening in April?

> The German bishop and witch hunter, Peter Binsfeld (ca. 1540–ca.1600) wrote that Belphegor tempts through laziness. According to Binsfeld's Classification of Demons, Belphegor is the main demon of the deadly sin known as sloth in the Christian tradition. The anonymous author of the Lollard tract The Lanterne of Light, however, believed Belphegor to embody the sin of gluttony rather than sloth.

Yeah, hits too close to home.

Via https://en.wikipedia.org/wiki/Belphegor

Re: Prime numbers so memorable that people hunt for them

#33

Post by scotty79 »

dchichkov wrote: post #29

ChatGPT o1: https://chatgpt.com/share/678feedb-0b2c-8001-bd77-4e574502e4... > Thought about large prime check for 3m 52s: "Despite its interesting pattern of digits, 12,345,678,910,987,654,321 is definitely not prime. It is a large composite number with no small prime factors." Feels like this Online Encyclopedia of Integer Sequences (OEIS) would be a good candidate for a hallucination benchmark...

I think firmly marrying llms with symbolic math calculator/database, so they can check things they don't really know "by heart" would go a long way towards making them seem smart.

I really hope Wolfram is working on LLM that is trying to learn what it means to be WolframAlpha user.

Re: Prime numbers so memorable that people hunt for them

#34

Post by lambertsimnel »

...in decimal.

https://t5k.org/notes/words.html points out that "When we work in base 36 all the letters are used - hence all words are numbers." Primes can be especially memorable in base 36. "Did," "nun," and "pop" are base-36 primes, as is "primetest" and many others.

Re: Prime numbers so memorable that people hunt for them

#35

Post by zellyn »

susam wrote: post #13

As soon as I read the title of this post, the anecdote about the Grothendieck prime came to mind. Sure enough, the article kicks off with that very story! The article also links to https://www.ams.org/notices/200410/fea-grothendieck-part2.pd... which has an account of this anecdote. But the article does not reproduce the anecdote as stated in the linked document. So allow me to share it here as I've always found it q…

One of my pet hobbies is trying to figure out the least prime prime number and most prime composite numbers under 100.

My votes are 61 or 89 for least prime-seeming primes and 87 and --yep-- 57 for more prime-seeming composites.

Re: Prime numbers so memorable that people hunt for them

#37

Post by WorldMaker »

TeMPOraL wrote: post #31
lehi wrote: post #3

https://en.wikipedia.org/wiki/Belphegor%27s_prime "666" with 13 0's on either side and 1's on the ends.

> Belphegor (or Baal Peor, Hebrew: בַּעַל-פְּעוֹר baʿal-pəʿōr – “Lord of the Gap”) is, in the Abrahamic religions, a demon associated with one of the seven deadly sins. According to religious tradition, he helps people make discoveries. He seduces people by proposing incredible inventions that will make them rich. Huh. Would feel right at home in our industry. > According to some demonologists from the 17th century,…

> Any demo days or other significant VC stuff happening in April?

Lots of tech companies plan elaborate demos for April 1st, for some foolish reason. It certainly gets very busy on HN keeping up.

Re: Prime numbers so memorable that people hunt for them

#38

Post by gregschlom »

On the topic of palindromic numbers, I remember being fascinated as a kid with the fact that if you square the number formed by repeating the digit 1 between 1 and 9 times (e.g. 111,111^2) you get a palindrome of the form 123...n...321 with n being the number of 1s you squared.

The article talks about a very similar number: 2^31-1, which is 12345678910987654321, whereas 1111111111^2 is 12345678900987654321

Re: Prime numbers so memorable that people hunt for them

#39

Post by ColinWright »

gregschlom wrote: post #38

On the topic of palindromic numbers, I remember being fascinated as a kid with the fact that if you square the number formed by repeating the digit 1 between 1 and 9 times (e.g. 111,111^2) you get a palindrome of the form 123...n...321 with n being the number of 1s you squared. The article talks about a very similar number: 2^31-1, which is 12345678910987654321, whereas 1111111111^2 is 12345678900987654321

You have misunderstood or mis-read the article ... 2^{31}-1 is not 12345678910987654321.

Specifically, 2^{31}-1 = 2147483647.

Borel asked Dyson to name a prime number and, unlike Grothendieck, Dyson provided a number that is only divisible by 1 and itself: 2^{31) – 1.

But that reply did not satisfy Borel. He wanted Dyson to recite all of the digits of a large prime number.

Dyson fell silent, so after a moment, Sloane jumped in and said, “1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1.”

So Sloane was supplying a different prime, but one where he could recite all the digits.

Re: Prime numbers so memorable that people hunt for them

#40

Post by xigoi »

zellyn wrote: post #35
susam wrote: post #13

As soon as I read the title of this post, the anecdote about the Grothendieck prime came to mind. Sure enough, the article kicks off with that very story! The article also links to https://www.ams.org/notices/200410/fea-grothendieck-part2.pd... which has an account of this anecdote. But the article does not reproduce the anecdote as stated in the linked document. So allow me to share it here as I've always found it q…

One of my pet hobbies is trying to figure out the least prime prime number and most prime composite numbers under 100. My votes are 61 or 89 for least prime-seeming primes and 87 and --yep-- 57 for more prime-seeming composites.

I once wrote in a Math Olympiad solution that 87 is prime. Not my brightest moment.
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