Crayon picture-book Pythagorean theorem
A 39-second explainer of the Pythagorean theorem drawn like a crayon picture book, made in JavaScript by Claude Opus 5.5 from a one-line Japanese instruction. A short prompt for the hand-drawn sketch look.
30秒くらいのピタゴラスの定理の解説動画をJavaScriptで作って（絵本風、クレヨン手書き風）
Make it yours. Swap ピタゴラスの定理 (the Pythagorean theorem) for another topic and 30秒くらい (about 30 seconds) for a length. The style words are in the brackets: 絵本風、クレヨン手書き風 (picture-book style, hand-drawn crayon style).
You'll need
- A browser to play the JavaScript, and a screen recorder for a video file
How it was made
The post presents the video as what came out of this one instruction; how the JavaScript was turned into a video isn't stated. The same creator posted a version of the same request that allowed ghost reference images, and a Riemann hypothesis explainer with the added rule not to include mathematical errors.
Posted Sep 23, 2026 · X · 38 likes · 36k views
Prompt from: Post body, in corner brackets
Look notesby Reference
A crayon-on-paper proof of the Pythagorean theorem: a right triangle, colored squares on its sides, four triangles in an a + b square around a tilted c² square, the triangles rearranged to leave a² and b², and a 3-4-5 check with counted grid squares.
- Color
- Cream paper with black crayon outlines and diagonal crayon shading: blue for a², orange for b², green for c², and violet triangles, plus a red underline and pale yellow highlighter strips behind the captions.
- Type
- Handwritten Japanese in a crayon style: the title "ピタゴラスの定理" underlined in red at top left, two-line captions on yellow strips at the bottom ("直角三角形の3辺を a, b, c とします"), and a closing "a² + b² = c²" written large, each letter in its square's color.
- Framing
- A 4:5 portrait page with a soft shadow at its edge, the title at top left, one diagram centered in the middle, and the caption strip centered near the bottom.
- Structure
- A right triangle ("直角三角形の3辺を a, b, c とします"), squares on each side asking "a² + b² = c² は本当かな？", a nearly blank page captioned "一辺 a + b の正方形に、同じ三角形を4つ置きます", the tilted green c² square between four triangles, the triangles partly moved ("三角形を動かして並べ替えてみると…"), the gaps now a² and b², "三角形4つは同じだから、すき間の面積も等しい", the equation over three grid squares, and "9 + 16 = 25" for a 3, 4, 5 triangle with gold stars.
