Fermat's little theorem | Journey into cryptography | Computer Science | Khan Academy

Introduction to a key result in elementary number theory using a visualization with beads
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[@user-2d2klem3nei]

THe most intuitive explanation I've seen so far, now I'll never forget this theorem. Thank you!

[@luce_9801]

It's an really Awesome combinatorial proof Hats Off Khan Academy Labs!!!

[@wrstark]

This is an excellent demonstration.

[@fahrenheit2101]

That was awesome. Might need to rewatch for it to fully stick in but this is the best intuitive explanation I've come across. I'd love to see how a more rigorous proof matches up with the logic used here.

[@funnywaves8765]

Please donate to Khan Academy so that they can keep their good work and provide more free Education worldwide for our Children of the Beautiful Planet.

[@mayankjangid1543]

GORGEOUS !!!!!! YOU MADE IT SO OBVIOUS. THANK YOU FOR YOUR EFFORTS !

[@valentinsarmagal]

that was beautiful, thank you

[@juicyclaws]

this is such a fucking good explanation

[@herzallahaymen5478]

The most beautiful mathematical proof I have ever seen in my life

[@subhajitbag5592]

This is stupendous!!💜

[@joshitasharma3102]

Wow, thank you so much😊

[@randomvideos3628]

you gotta be kidding me... this is awesome!

[@ingrid1156]

Stunning explanation

[@MrAnandabhyankar]

Great Work!!

[@theSpicyHam]

Whoa it's true, works with any numbers

[@santoshnegi5693]

I never thought this way It was interesting

[@jasonzacharias2150]

Thank you sir, thank you...

[@minyihuang225]

Amazing video!

[@tech_aashish]

This is god level explination 😍

[@Jomodev]

Great Explanation

[@nicolasmagee1780]

The 9th row in the 2:06 seems to be repeated with the 7th row :)

[@wiscatbijles]

Yes, should have been 1001. That's the permutation that was missing.

[@Kira-yn9fs]

@@wiscatbijles exactly!

[@feroze170]

Brit your videos allow me to understand, which sparks my interest in the subject, which opens up a whole new world to me.

[@luce_9801]

They really are too good for not to generate interest for the topic.

[@jacksonkaib5122]

Why does the last part of the explanation make sense? How does (a^p)|a = x remainder a ?

[@chaussebenjamin]

2:00 Didn't you forget the sequence pyyp (p=purple, y=yellow) for the sequences containing 2 of each color?

[@miketurner3461]

It divides evenly into cosets of size 3 which themselves groups but there is only one proper subgroup right?

[@sk99gaming99]

so can i say that the number of arrangemnts are n-1!/2

[@lafudge2929]

0:33

[@ehza]

😎

[@shramanabhattacharya5136]

So what I inferred from the last part was that when the monocoloured beads are subtracted,then exactly 'a' no. of strings are removed.But a is supposed to be the no. of type of colours used.I am confused.... But otherwise it was a good explanation.

[@udayrallabhandi3345]

Abhijit Bhattacharyya Because for every color, there is one string that is only made up of beads of that color

[@eobardthawne6903]

Oh shit! My university professors should watch these videos first before teaching us.

[@vighneshk509]

fucking amazing !!!

[@SCOA57KrutikaAhire-en1ob]

this rule doesn't seem fundamental to me

[@gouravbansal3391]

That was ridiculous

[@flanker53]

watching at 1.5 speed why u talk so slow...good video anyways