Moving visuals on this page — measured at 0.26% brightness change per frame and zero flashes per second; your reduce motion setting stops them. What moves, and how it was measured

Mathematical plates that draw themselves — prime counts, orbits and lattices rendered live rather than shipped as pictures. It runs continuously while on screen, and it pauses on its own whenever it scrolls out of view.

We measured it rather than guessing: the largest frame-to-frame change in average brightness is 0.26%, and it produces zero flashes per second against the threshold of three set by WCAG 2.3.1. That is well under the limit, and it is not a promise about any individual: if moving images are a problem for you, you should not have to assess ours.

Everything animated on this site honours your system’s reduce motion setting — turn it on in your operating system or browser and these pages stop moving, with nothing else lost. All the mathematics is in the text and the still figures.

Free tools

Three small, self-contained tools — run the mathematics yourself

Everything below runs entirely in your browser, in exact arithmetic where it matters (JavaScript BigInt, never floating point for the math itself). No account, no tracking, no data leaves your tab. Each one has its own page: no museum to walk through first. If you would rather read about the mathematics than run it, that is what The Notebook is for.

What just ran, verified

Not marketing figures — real counts from these three tools' own test runs

0network requests made by any tool above
0cookies set by this page — the 3 tools above do write a local-only fair-use counter to localStorage per run (never sent anywhere, see note above their buttons), which is not nothing, so we're not calling it zero
2998integers cross-checked against independent trial-division primality
41/41Collatz steps verified individually, not just the final value

All three tools above are pure functions of what you type — nothing is sent anywhere, checkable yourself: open your browser's Network tab and use them offline.