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@article{JIS_2017__20_6_a5, author = {Iannucci, Douglas E.}, title = {On the equation $\sigma (n) = n + \phi (n)$}, journal = {Journal of integer sequences}, publisher = {mathdoc}, volume = {20}, number = {6}, year = {2017}, language = {en}, url = {http://geodesic.mathdoc.fr/item/JIS_2017__20_6_a5/} }
Iannucci, Douglas E. On the equation $\sigma (n) = n + \phi (n)$. Journal of integer sequences, Tome 20 (2017) no. 6. http://geodesic.mathdoc.fr/item/JIS_2017__20_6_a5/