Shiitake 1y ago • 100%
Waaaait a second.
Does that hold for every base, where the divisor is 1 less than the base?
Specifically hexidecimal - could it be that 5 and 3 have the same "sum digits, get divisibility" property, since 15 (=3*5) is one less than the base number 16?
Like 2D~16~ is16*2+13 = 45, which is divisible by 3 and 5.
Can I make this into a party trick?! "Give me a number in hexidecimal, and I'll tell you if it's divisible by 10."
Am thinking it's 2 steps:
- Does it end with a 0, 2, 4, 6, 8, A, C, E? Yes means divisible by 2.
- Do the digits add up to a multiple of 5 (ok to subtract 5 liberally while adding)? Skip A and F. For B add 1; C->2, D->3, E->4. If the sum is divisible by 5, then original number is too.
So if 1 and 2 are "yes", it's divisible by 10.
E.g.
- DEADBAE~16~ (=233495470~10~): (1) ends with E, ok. (2) 3+4+3+1+4=15, divisible by 5. Both are true so yes, divisible by 10.
- C47444~16~ (=12874820~10~): (1) ends with 4, ok. (2) 2+4+7+4+4+4=25, ok.
- BEEFFACE~16~ (=3203398350): (1) E, ok. (2) 1+4+4+2+4=15, ok.
Is this actually true? Have I found a new party trick for myself? How would I even know if this is correct?
Shiitake 1y ago • 100%
OW!!
Upstoated!
Shiitake 1y ago • 100%
Ayy me too
Upcontent!
Shiitake 1y ago • 100%
I choose you, Pikachu!
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Shiitake 1y ago • 100%
Welcome! I'm also pretty new.
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Shiitake 1y ago • 100%
NO! I AM A SIMPLE MAN AND I LIKE THIS MEME
Uproaded!
Shiitake 1y ago • 100%
you shall have it
Upkroated!
Shiitake 1y ago • 100%
Hold on!!
Upcloated!
Shiitake 1y ago • 100%
Hello
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Shiitake 1y ago • 100%
Something something upstroated!
Shiitake 1y ago • 100%
I don't know but hello!
Upkoded!
Shiitake 1y ago • 100%
Oo interesting, I'll have to check that out. Thanks for the tip!
Updotted!
Shiitake 1y ago • 100%
No, there is lunch, lies and uploading. Just kidding - have an upvote!
Upvobed!
Shiitake 1y ago • 100%
Thanks!!
Uppoodled this reply!
Shiitake 1y ago • 100%
Exactly! Many thanks, and have an upvote!
Upkoated!
Shiitake 1y ago • 100%
Hi, Dad!! Tell Mom I said hi too!!
Uphooted!
Shiitake 1y ago • 100%
Many thanks! And my axe!!
Upxoted!
Shiitake 1y ago • 100%
Hi! I'm glad <3
Uploated!
Shiitake 1y ago • 100%
Whoa someone looked!! Thanks!!
Updooted!
Shiitake 1y ago • 100%
![your alt text here](http://link/to/pic.jpg)
^Like that!
Uppoated!
![Ron Swanson meme where he says "I'm a simple man". He's looking at the camera, in a brown suit, with a sexy mustache and very slight smirk. Background is blurry paintings. Caption says "I'm a simple man" at the top and "I see a reply, I upvote it" at the bottom. End description.](https://i.imgflip.com/7rpmbp.jpg)
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