Mathematicians Of The Day

17th October

On this day in 1952, D H Lehmer announced that 2n12^{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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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.
Quoted in H Eves Mathematical Circles Squared (Boston 1972).