## Mathematicians Of The Day

### 27th July

On this day in 1837, Lejeune Dirichlet presented his first analytic number theory paper at a meeting of the Berlin Academy of Sciences. He proved the fundamental theorem that bears his name:

*Every arithmetical sequence an + b, n = 0, 1, 2, ... of integers, where a and b are relatively prime, contains infinitely many primes.*
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##### Born:

- 1667: Johann Bernoulli Ⓟ
- 1801: George Airy Ⓟ
- 1844: Ágoston Scholtz
- 1848: Lóránd Eötvös Ⓟ
- 1849: John Hopkinson Ⓟ
- 1867: Derrick Norman Lehmer Ⓟ
- 1871: Ernst Zermelo Ⓟ
- 1879: David Picken Ⓟ
- 1902: Reuben R McDaniel Ⓟ
- 1921: Jonas Kubilius Ⓟ
- 1930: Ismail Mohamed Ⓟ

##### Died:

- 1759: Pierre-Louis Moreau de Maupertuis Ⓟ
- 1870: Pierre-Joseph-Étienne Finck
- 1931: Jacques Herbrand Ⓟ
- 1987: Jan Mikusiński Ⓟ
- 1999: Aleksandr Aleksandrov Ⓟ
- 2015: J W S Cassels Ⓟ
- 2021: Enrique Planchart Ⓟ

#### Quotation of the day

##### From George Airy

On Sept 15th [1852] Mr Goulburn, Chancellor of the Exchequer, asked my opinion on the utility of Mr Babbage's calculating machine, and the propriety of spending further sums of money on it. I replied, entering fully into the matter, and giving my opinion that it was worthless.