Solved cryptogram
Add one over each square number, forever, and the total involves pi. Nobody expected that.
Mathematics Facts, sourced to Wolfram MathWorld.
Solve it yourself
This fact is a cryptogram here: 72 letters over 21 different ones, graded hard.
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What it means
The sum of one, a quarter, a ninth, a sixteenth and onward comes to pi squared over six. The question stood open for ninety years and made Euler's name when he answered it in 1735. The astonishing part is the pi. Nothing in the question mentions a circle, and the answer arrives carrying one anyway, which is the first hint most people meet that the different corners of mathematics are secretly the same building.
The claim comes from Wolfram MathWorld.
- SourceWolfram MathWorld
- CollectionMathematics Facts
- Difficultyhard
- Length72 letters, 21 of them different
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