N._G._W._H._Beeger

Nicolaas George Wijnand Henri Beeger (1884, in Utrecht – 1965, in Amsterdam) was a Dutch mathematician. His 1916 doctorate was on Dirichlet series. He worked for most of his life as a teacher, working on mathematics papers in his spare evenings. After his retirement as a teacher at 65, he began corresponding with many contemporary mathematicians and dedicated himself to his work. Tilburg University still holds biennial lectures entitled the Beeger lectures in his honour.
He is known for having proved that 3511 is a Wieferich prime in 1922 and for introducing the term Carmichael number in 1950.