## Mathematicians Of The Day

### 30th June

On this day in 1742, Leonard Euler claimed in a letter to Goldbach that prime numbers of the form 4

He also mentioned that 641 divides $2^{32} + 1$, thereby disproving Fermat's claim that all the so-called numbers Fermat numbers $F_n = 2^{2^n} + 1$ are prime. Years later we have not found another with

*n*+ 1 are represented uniquely as a sum of two squares.He also mentioned that 641 divides $2^{32} + 1$, thereby disproving Fermat's claim that all the so-called numbers Fermat numbers $F_n = 2^{2^n} + 1$ are prime. Years later we have not found another with

*n*> 4 which is prime.
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##### Born:

- 1748: Dominique Cassini Ⓟ
- 1791: Félix Savart Ⓟ
- 1846: Eugen Netto Ⓟ
- 1856: Cargill Knott Ⓟ
- 1868: Geoffrey Bennett Ⓟ
- 1876: Anton Davidoglu Ⓟ
- 1880: Rudolf Fueter Ⓟ
- 1900: Gheorghe Vrănceanu Ⓟ
- 1907: Dmitrii Konstantinovich Faddeev Ⓟ
- 1923: Murray Macbeath Ⓟ
- 1958: Abigail Thompson Ⓟ

##### Died:

- 1817: Li Rui
- 1919: John William Strutt Ⓟ
- 1960: Albert Châtelet Ⓟ
- 1972: Yuri Vladimirovich Linnik Ⓟ
- 2002: Claude Berge Ⓟ
- 2019: Mitchell Feigenbaum Ⓟ

#### Quotation of the day

##### From John William Strutt

Examples ... which might be multipliedad libitum, show how difficult it often is for an experimenter to interpret his results without the aid of mathematics.