Weird Number | Hacker News Reader

Weird Number

en.wikipedia.org

70 pointsbenbreen28 comments

I do believe mathematicians have co-opted a great many dictionary words to describe obscure and unique properties of numbers, so they may converse at parties and from a distance it sounds like a normal conversation.

Yes, but if you talk continuously about these sorts of things, it's impossible to be discrete.

Pun intended?

Nothing but the pun is intended!

It's because number theory is ancient. The concept of primality is millennia old. The words used to describe numbers are thus built up over a very long time, and often were meant to evoke imagery, concepts, or even personalities.

If you examine younger branches of mathematics with fewer numbers, like topology or category theory, you will find more systematically-named rules and more systems named for people. The list of separation axioms [0] is the best-known example.

[0] https://en.wikipedia.org/wiki/Separation_axiom

I think the only mathematics joke that I've come up with myself is "Almost-all numbers are normal" - a self-evidently true statement, which nevertheless means something wildly different than what a layman might believe - indeed, the numbers that a non-mathematician might be most likely to imagine or name are in fact not normal!

The anthropomorphization of numbers is strange. It seems awfully subjective to describe numbers meeting certain qualities as "weird".

Wait until you find out what "awfully", "subjective", "certain", and "qualities" mean to mathematicians.

Also inconsisten. https://www.merriam-webster.com/dictionary/weird says:

”Definition of weird (Entry 1 of 2)

1 : of strange or extraordinary character : ODD, FANTASTIC”

But FTA: ”It is not known if any odd weird numbers exist”

Was introduced to this idea a while ago by the venerable Boards of Canada: https://bocpages.org/wiki/The_Smallest_Weird_Number

Thanks for this! I've been a BoC fan since 2000 after discovering "Music Has The Right To Children", I think in part due to John Peel. Amazingly this site has slipped under my radar. Hard to believe it's 20+ years since that album was released.

Right on. Yeah, I got into them in the 90s thanks to the odd way in which Napster introduced me to new music. Typically I'd find an electronic artist, search for them, and find songs by them on compilation albums or on mixtapes that people had painstakingly separated into tracks with good ID3s. Download those whole albums, listen, and then whatever was good from them, I'd put back into the system. It was sort of like manually crawling through a curated recommendations graph.

Ironically, it made me buy a ton of CDs, so the industry probably made more off me than if I'd had no access to this sort of thing. $50 import British double-CDs off Warp Records et al? You know I was shelling out for it. Beautiful Warp20 collection with an unheard, virgin-vinyl cut from Boards of Canada? How could I not, back when I was younger and had disposable income?

The cult aspect of BoC is what turned me into a follower, because there's all these insane references that add a ton of depth to the music that still isn't really there with most of the artists that have filled the space they carved out.

It seems like the observation that all known weird numbers are even is almost built-in to the definition of weirdness.

Having two as a prime factor is the single most effective way to increase the number of integer divisors, as it is the smallest integer that you can multiply by a larger prime to get a product different from both operands. If there is an odd weird number larger than 10^21, the first one found would probably be divisible by 3.

Finding the first primitive odd weird number seems like something you could put on a CV.

Clifford Pickover has some really interesting books about numbers, including The Wonders of Numbers or the Loom of God: http://sprott.physics.wisc.edu/pickover/noodlead.html

I hate to call a single Wikipedia user out, but every time I see a diagram on a math or science related wiki page that does absolutely nothing to contribute to an understanding of the topic and in fact only serves to confuse the viewer, it always ends up having been made by https://commons.wikimedia.org/wiki/User:Cmglee

A lot of the time, I think it's better to simply not have any visual on a wiki page than to have an utterly unhelpful visual.

This diagram makes perfect sense to me, it shows many counterexamples to possible subset relations and suggests some possible subset relations by lack of counterexample.

Edit: I can't believe that someone deleted it from the Wiki page. If you deleted everything on Wikipedia that at least one person didn't understand you would be left with nothing, and definitely nothing related to math...

> Removed the diagram that showed various weird numbers. Before reverting, please examine the diagram and ask yourself honestly whether it is helpful to any reader or merely serves to befuddle and muddy the waters of understanding!

How completely... arrogant.

Here’s the Weird number Wikipedia entry with the diagram, as it seems to have been edited out very recently by an anonymous editor:

https://en.m.wikipedia.org/w/index.php?title=Weird_number&di...

What anon taketh away, anon giveth back. Long live Wikipedia

The definition of a weird number is one that is abundant but not semiperfect.

I looked for the "semiperfect" label on that stupid fucking diagram for like three minutes.

It isn't fucking there. That diagram can burn in the library of shitty diagrams.

I'll admit the diagram is complex and takes some time to understand, but that's the nature of mathematics. You cannot skim mathematics. You must parse each and every symbol, and understand all of the parts before you have any hope of comprehending the totality.

The diagram is quite helpful in showing the relationships between these peculiar sets of numbers. And it took me a minute to grok it

someone removed the diagram.

Some folks are visual learners, it seems petty and mean to just remove diagrams because they don't fit with your mode of learning.

The diagram looks helpful to me

https://en.wikipedia.org/w/index.php?title=Weird_number&diff...

There are quite a few users on wikipedia that seem to have a niche that they really hammer on. They do one operation that they know well over many hundreds of articles. I don't know why they do it. Perhaps to get huge edit numbers for their account.

I found the diagram highly illuminating, much moreso than the text.

Without the diagram, it reads like mush. With, it becomes clear how peculiar (not to say odd, or weird) 70 is.

> Examples

> The smallest weird number is 70. Its proper divisors are 1, 2, 5, 7, 10, 14, and 35; these sum to 74, but no subset of these sums to 70. The number 12, for example, is abundant but not weird, because the proper divisors of 12 are 1, 2, 3, 4, and 6, which sum to 16; but 2 + 4 + 6 = 12.

Why are they called weird?

Because most numbers that are abundant are semi perfect. Weird numbers are abundant but -not- semi perfect.

example 312-202-9901

home recording????

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