Stefanutti experimental homepage

Links and webapps

Pick where to dive in.

A historical map of Königsberg with the river Pregel and its seven bridges highlighted in yellow — the Seven Bridges of Königsberg.
Mathematics · Reference External

Four Color Theorem

The companion site with the full background, history, and proof narrative behind the four-coloring of planar maps.

Visit four-color-theorem.com
A sphere covered by a planar map of colored regions, in the style of the Four Color Theorem.
Mathematics · Visualization

Waterworld Colonization

Watch a cubic planar map grow, region by region, across a globe — a visual proof of the invariant behind the Four Color Theorem.

Open the visualization
Sumi-e illustration of two Aikido practitioners on warm cream paper with a vermilion brushstroke.
Martial arts · Catalog

合気道 · Aikido

An interactive catalog of the techniques in the ProgettoAiki Dan exam syllabus, organized by category with reference videos.

Browse the techniques
A cubic planar graph with two green split nodes flanking a glowing orange bridge edge.
Graph theory · Interactive

Split & Bridge

An interactive planar graph editor for splitting edges and exploring bridge connections.

Open the graph editor