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 4n+ 1 are represented uniquely as a sum of two squares.
He also mentioned that 641 divides 232+12^{32} + 1, thereby disproving Fermat's claim that all the so-called numbers Fermat numbers Fn=22n+1F_n = 2^{2^n} + 1 are prime. Years later we have not found another with n > 4 which is prime.

Click on for a poster.


Quotation of the day

From John William Strutt
Some proofs command assent. Others woo and charm the intellect. They evoke delight and an overpowering desire to say, "Amen, Amen".
Quoted in H E Hunter The Divine Proportion (New York 1970)