## Mathematicians Of The Day

### 17th October

On this day in 1952, D H Lehmer announced that $2^{n-1}$ for

*n*= 2203 and 2281 are Mersenne primes. He was aided by a SWAC computer, with the first result taking 59 minutes. SWAC had been built in 1950 in Los Angeles.
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##### Born:

- 1759: Jacob (II) Bernoulli Ⓟ
- 1808: Philip Kelland Ⓟ
- 1870: David J Tweedie
- 1888: Paul Bernays Ⓟ
- 1927: Friedrich Hirzebruch Ⓟ

##### Died:

- 1817: John West
- 1887: Gustav Kirchhoff Ⓟ
- 1923: August Adler
- 1937: Frank Morley Ⓟ
- 1952: Ernest Vessiot Ⓟ
- 1963: Jacques Hadamard Ⓟ
- 1976: Edward Marczewski Ⓟ
- 1978: Gertrude Cox Ⓟ
- 1989: Mark Krein Ⓟ
- 2008: Andrew Gleason Ⓟ

#### Quotation of the day

##### From Jacques Hadamard

Practical application is found by not looking for it, and one can say that the whole progress of civilization rests on that principle.