About

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Built with

SvelteKit, p5.js, D3, Cytoscape.js, Tone.js, and Lucide icons; type is Inter. The code is under the Blue Oak Model License; the libraries and fonts keep their own — see the third-party notices.

Attribution is appreciated.

Why

This site was made mostly for personal use in mentoring, sharing, and facilitating math, and to embed interactive toys in blog posts on FractalKitty.

A lot of what is built is out of wanting to understand and play with concepts and to add to resources for others.

I am grateful to the Recurse Center for the space and community that have contributed in my learning about Svelte, D3, licenses and so much more.

Contact

If there is an error, something missing, or suggestions, feel free to reach out. If you wish to request a tool or toy, please reach out through my contact page.

If I have bandwidth and it makes sense I'll try to find time to spin it up.

I only consider tools that are Creative Commons or public domain, in line with open education, not widely available, and will benefit others.

Sources

Math & ideas

• “A chiral aperiodic monotile” — Smith, Myers, Kaplan & Goodman-Strauss (the homepage map)
• Natural Math (the puzzle behind Moduloku)
• James Grime, “Kruskal's Count”
• The catenary and its inverted arch (the model behind Hang On)
• René Alderliesten, “Cables” (TU Delft Open) — chains carrying point weights
• Block, DeJong & Ochsendorf, “As Hangs the Flexible Line” (Nexus Network Journal, 2006)
• Gaudí's hanging-chain model for the Colònia Güell church
• Squaring the square — Duijvestijn's order-21 perfect square (1978), Dudeney's Mrs. Perkins's quilt, and Bouwkamp's notation (behind Squarrel Numbers)
• “Squarable Numbers” — Math for Love (a lovely lesson on the same question)
• W. T. Tutte, “The dissection of equilateral triangles into equilateral triangles” (1948) — no such dissection has every piece a different size (behind Trianglable Numbers)
• J. H. Conway, “An enumeration of knots and links, and some of their algebraic properties” (in Computational Problems in Abstract Algebra, Pergamon, 1970, pp. 329–358) — where a tangle's fraction and Conway notation come from (behind Tangle Truchet)
• Kauffman & Lambropoulou, “On the classification of rational tangles” (Advances in Applied Mathematics, 2004) — two rational tangles are the same tangle exactly when their fractions agree, proved once by coloring
• Fox n-colorings (Ralph Fox, 1956) — the rule at a crossing that Tangle Truchet solves to read a fraction off a drawing

Algorithms & code

• Matthew Kaplan and Elaine Cohen, “Computer Generated Celtic Design”
• mulberry32 PRNG (Tommy Ettinger) and cyrb53 hash (bryc)
• Catmull–Rom splines (Catmull & Rom, 1974)