math

804 readers

12 users here now

General community for all things mathematics on @lemmy.world

Submit link and text posts about anything at all related to mathematics.

Questions about mathematical topics are allowed, but NO HOMEWORK HELP. Communities for general math and homework help should be firmly delineated just as they were on reddit.

founded 1 year ago

MODERATORS

mrh@lemmy.world

Is there a name for numbers whose only factors are primes and semiprimes but may not be primes in themselves? (lemmy.world)

submitted 1 year ago by favrion@lemmy.world to c/math@lemmy.world

4 comments fedilink hide all child comments

And for how long can this pattern continue?

you are viewing a single comment's thread
view the rest of the comments

[–] nadiaraven@lemmy.world 3 points 1 year ago (1 children)

How long can this pattern continue? My guess is forever, since you can just multiply a prime by the next prime (2x3=6), then take that prime, and multiply it by the next (3x5=15) and so on. So it seems to me like there's an infinite number of these kinds of primes, unless I'm not understanding you correctly.

[–] milicent_bystandr@lemm.ee 0 points 1 year ago

I guess they mean a naming pattern: like hemi-demi-semi-primes

(That's how we do it in music, over on my side of the 'pond': but we get to hemi-demi-semi-quavers then (afaik) give up because no one cares for more!)