The pen-and-paper tag has no wiki summary.
1
vote
2answers
93 views
Is there any strong enough pen-and-paper or mind cipher?
Some ciphers are talked about here, but I don't see an answer, are they strong enough, or are non-computer ciphers more or less just a toy and one should abandon using them for practical purposes?
3
votes
2answers
189 views
toy hash algorithm
I'm looking for a toy hash function, where the idea is to have high school students break (i.e. find a collision) a hash function by hand, in order to teach them how one way functions and hashing ...
0
votes
0answers
77 views
computing inverses in truncated polynomial rings manually for NTRU encryption
Can someone explain how to find inverses in truncated polynomial rings manually (i.e. on pen and paper)?
As an example from the tutorial:
Example. Take $N=7$, $q=11$, $a=3+2X^2-3X^4+X^6$. The ...
