# Basel problem

Definition from Wiktionary, the free dictionary

## English[edit]

### Noun[edit]

**the Basel problem** (*uncountable*)

- (mathematics) The question as to the value of , the sum of the reciprocals of the squares of the positive integers.
**1999**, William Dunham,*Euler: The Master of Us All*, Mathematical Association of America, ISBN 0883853280, page 55,- As noted, some of Euler's contemporaries, while accepting his answer to the
**Basel Problem**, wondered about the validity of the argument that got him there.

- As noted, some of Euler's contemporaries, while accepting his answer to the
**2005**, Rajendra Bhatia,*Fourier Series*, Mathematical Association of America, ISBN 0883857405, section 3.10, page 75,- Solving
**the Basel problem**was one of the early triumphs of L. Euler (1707–1783)... .

- Solving
**2007**, Charles Edward Sandifer,*The Early Mathematics of Leonhard Euler*, Mathematical Association of America, ISBN 0883855593, page 165,- And so ends one of Euler's most famous papers. We see that Euler actually solves the
**Basel problem**three times and that he does much more.

- And so ends one of Euler's most famous papers. We see that Euler actually solves the