4
votes
1answer
85 views

Are there any secure ciphers you can use without a computer?

I have some kids that like encryption schemes such as the Caesar cipher and the Vigenère cipher. I would like to teach them something that's not easily breakable by todays maths and computers, but I ...
2
votes
2answers
477 views

How to handle big powers on big numbers e.g. $n^{915937897123891}$

I'm struggling with the way to calculate an expression like $n^{915937897123891}$ where $n$ could be really any number between 1 and the power itself. I'm trying to program (C#) this and therefor ...
2
votes
1answer
472 views

Calculate the root of a number without useing the root function or decimal numbers

I'm trying to build a program in c# which will calculate prime numbers for me. I'm using the BigInteger class to work with 'endless' numbers. However, there is a big down side on this function, I ...