Naslov
On a variation of a congruence of Subbarao

Autori
Dujella, Andrej ; Luca, Florian

Izvornik
Journal of the Australian Mathematical Society (1446-7887) 93 (2012), 1/2; 85-90

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Euler function; sum of divisors; Pellian equations

Sažetak
Here, we study positive integers n such that n*phi(n) = 2 (mod sigma(n)), where phi(n) and sigma(n) are the Euler function and the sum of divisors function of the positive integer n, respectively. We give a general ineffective result showing that there are only finitely many such n whose prime factors belong to a fixed finite set. When this finite set consists only of the two primes 2 and 3 we use continued fractions to find all such positive integers n.

Izvorni jezik
Engleski

Znanstvena područja
Matematika

POVEZANOST RADA