[Todos] Recordatorio: Coloquios del Departamento de Matemática

[Daniel Carando]

Próxima charla:
Hoy Jueves 17 de abril a las 16:00, aula E-24

 Paul Loomis
 Bloomsburg University


 A survey of the sum of totients function

 We begin with the function $F(n)=\phi(n)+\phi(\phi(n))+\dots+1$, where
 $\phi(n)$ is the Euler totient function. A perfect totient number n is
 one for which $F(n)=n$. Perfect totient numbers have an interesting
 history, beginning with a paper written (in Spanish) by L. Perez Cacho
 in 1939, followed by decades of papers in English by authors unaware
 of this work. We raise several questions (and answer some) about
 $F(n)$; techniques used range from undergraduate-level classical
 number theory to modern analytic number theory.


 Están todos cordialmente invitados.