this post was submitted on 11 Dec 2024
605 points (95.5% liked)

People Twitter

6131 readers
720 users here now

People tweeting stuff. We allow tweets from anyone.

RULES:

  1. Mark NSFW content.
  2. No doxxing people.
  3. Must be a pic of the tweet or similar. No direct links to the tweet.
  4. No bullying or international politcs
  5. Be excellent to each other.
  6. Provide an archived link to the tweet (or similar) being shown if it's a major figure or a politician.

founded 2 years ago
MODERATORS
[email protected]
[email protected]
605
It looks so wrong (sh.itjust.works)
submitted 2 months ago by [email protected] to c/[email protected]
72 comments fedilink hide all child comments
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 22 points 2 months ago (1 children)

The digit sum of 51 is 6, which is divisible by three. So 51 is also divisible by three. It’s not even hard to see that it’s not prime.

[–] [email protected] 15 points 2 months ago* (last edited 2 months ago) (1 children)

Yup, my personal prime check is:

  1. Even?
  2. Ends in 5?
  3. Digits sum to 3?

If it fails all three and it's not an "obvious" prime (<20), then it's prime enough for me.

[–] [email protected] 2 points 2 months ago (1 children)

Also

Ends in 0,

but that's covered by 5 really.

[–] [email protected] 7 points 2 months ago

It's also covered by being even.