Category Archives: Ciphers

Being simultaneously Christmas Day and Cipher Tuesday, I have a lot of material to get through. Isaacs Firstly, happy 370th birthday to Sir Isaac Newton, who succeeded Isaac Barrow as the Lucasian Professor of Mathematics (both from Trinity, yay!). This gives … Continue reading →

The inspiration for this cipher stemmed from a conversation with James Aaronson, when we considered the prospect of a whole new category of cipher. I was initially sceptical as to whether it could actually be implemented (they’re certainly much harder … Continue reading →

The RSA cryptosystem is named after Rivest, Shamir and Adleman, who rediscoved it at MIT. It was created earlier by Clifford Cocks at GCHQ, but that information was classified. It is an example of a trapdoor cipher (others include elliptic … Continue reading →

This particular cipher comes in two components (an image and some ciphertext), both of which you’ll need to successfully solve the challenge. If you delve deeper, you may find more hidden clues and secret images to help you decrypt this beast of … Continue reading →

Due to popular demand, the frequency of Cipher Tuesdays has increased from every four weeks to its theoretical limit of every week. Also by popular demand, this cipher is given as both an image (for manual solvers) and delineated text … Continue reading →

To make a welcome change from the monoalphabetic substitution ciphers embedded in images, I have decided to publish this particular cipher in a text-only format for ease of access. WII MJCVKWV FZN ZQLHWMH HA ZLH GMFKTJQ DKOQXT XM UNN LAADANPNFT EOWZXJRX … Continue reading →

Don’t forget that the MathsJam is today, held throughout the country and indeed the world. It is suprising that no-one has yet solved the maze cipher, and only one person has managed to assemble and decipher the Jigcypher. Perhaps I … Continue reading →

The Labyrinth usually refers to a particular maze in Knossos on the Greek island of Crete, designed by Daedalus to contain the Minotaur: a ravenous bull-human hybrid, which found human sacrifices particularly appetising. Theseus navigated these tortuous underground passageways by means of … Continue reading →

This is the first of a series of cipher challenges published at regular intervals. After much deliberation, I settled upon a 28-day cycle, for the benefit of both werewolves and pre-menopausal women alike. It is also a convenient multiple of … Continue reading →