RSA_numbers_factored/ (transpiled from RSA_numbers_factored.py, BigInt in browser)
R.html show all RSA numbers with both prime factors ≡1 (mod 4)
squares.html show square sums and diffs for RSA numbers and their prime factors
validate.html show all RSA number lengths, and do a lot of assert validations
https://hermann-sw.github.io/planar_graph_playground/
Planar graph playground
https://hermann-sw.github.io/cuboid_shortest_paths
Determine and visualize shortest paths between single point on bottom face and many points on top face of cuboid
https://hermann-sw.github.io/javascript-sphere/
Simple 3D sphere JavaScript demo
https://stamm-wilbrandt.de/GraphvizFiddle/
<GraphvizFiddle/> (online Graphviz editor&layout [based on Viz.js])
https://stamm-wilbrandt.de/en/xsl-list/peg-solitaire/
It knows all solutions for 33/37/39 pegs English/French/3-3-2-2 boards.
You may choose "Cheat" link (based on 1+16+64=81GB data files on the website).
There are 2,990,375,067 good positions for French board that allow to end with single peg on target field (forum link).
Instructions on how to revert a move can be found just above that posting (animation):
https://stamm-wilbrandt.de/xqib/
("foobar" → "ɹɐqooɟ" [browser XQuery])
https://stamm-wilbrandt.de/en/xsl-list/n-queens/n-queens.xsl.xml
https://stamm-wilbrandt.de/echo-e.to.braille.html
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