Jacopo Notarstefano

Circuit Design

Your laboratory partner made a mess while designing the circuit boards for your experiment! Help them fix the issue by making sure that no connection crosses any other.

Solve this problem by clicking here.

Google Foobar: a Post Mortem

So, what was Google Foobar about? I still don't know. I will describe the problems I encountered, the techniques I used and what I learned. I will also discuss a few conjectures I have about it.

Read this post by clicking here.

Turing's sunflower

In a letter to the zoologist J.Z. Young, British mathematician Alan Turing announced that his theory of embriology could explain, among other things, the connection between leaf arrangements and Fibonacci numbers.

Discover a possible explanation by clicking here.


A sequence of integers \(d_1,\dots,d_n\) is called graphical if there exists a graph \(G\) with it as its degree sequence. A theorem by Erdős and Gallai characterizes which sequences are graphical, but gives no algorithm to explicitly construct such a graph. Can you construct it?

Solve this puzzle by clicking here.

Who killed the Duke of Densmore?

One day Sherlock Holmes received the visit of his friend Watson, who was asked to investigate on a murder that had gone unsolved for more than ten years. At the time, the Duke of Densmore had been killed by a bomb powerful enough to destroy the castle where he had been living since retirement.

Solve this mistery by clicking here.

Four-coloring a Dodecahedron

By the Four color theorem, the faces of a dodecahedron are four-colorable; that is, one can pick a color among four for each face in such a way that no two adjacent faces share the same color. But can you find such a coloration?

Solve this puzzle by clicking here.

Fork me on GitHub