In this note, we study those positive integers $n$ which are divisible by $\sum _{d|n}\lambda (d)$, where $\lambda (\cdot )$ is the Carmichael function.
@article{107979, author = {William D. Banks and Florian Luca}, title = {On integers with a special divisibility property}, journal = {Archivum Mathematicum}, volume = {042}, year = {2006}, pages = {31-42}, zbl = {1164.11050}, mrnumber = {2227110}, language = {en}, url = {http://dml.mathdoc.fr/item/107979} }
Banks, William D.; Luca, Florian. On integers with a special divisibility property. Archivum Mathematicum, Tome 042 (2006) pp. 31-42. http://gdmltest.u-ga.fr/item/107979/
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