KESAVA MENON, P. On the Sum Σ (a-1, n), [(a, n) = 1]. The Journal of the Indian Mathematical Society, [S. l.], v. 29, n. 3, p. 155–163, 1965. DOI: 10.18311/jims/1965/16834. Disponível em: http://informaticsjournals.com/index.php/jims/article/view/16834. Acesso em: 5 may. 2024.