# Basel problem

> English word · Proper noun

## Definitions
1. The question as to the value of ∑ₙ₌₁ ᪲1/(n²), the sum of the reciprocals of the squares of the positive integers.

## Etymology
Named after Basel, the home town of Euler and of the Bernoulli family who unsuccessfully attacked the problem.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/basel-problem