Lithuanian Mathematical Journal

, Volume 48, Issue 3, pp 316–321 | Cite as

A remark on a paper of F. Luca and A. Sankaranarayanan



We generalize a result of F. Luca and A. Sankaranarayanan by proving that the set of n for which ϕ(1) + ⃛ + ϕ(n) is squareful is of zero density. A similar statement holds for σ (n) instead of ϕ(n) and for some other multiplicative functions.


Euler’s totient function squareful integers 


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Copyright information

© Springer Science+Business Media, Inc. 2008

Authors and Affiliations

  1. 1.Department of Computer AlgebraEōtvōs Loránd UniversityBudapestHungary

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