References
- BATEMAN, P.—DIAMOND, H. G.: Analytic Number Theory—An Introductory Course. Monographs in Number Theory, Vol. 1, World Scientific Publishing Co. Pte. Ltd., Hackensack, NJ, 2004.
- BALASUBRAMANIAN, R.—LUCA, F.—RALAIVAOSAONA, D.: On the sum of the first n values of the Euler function,Acta Arith. 163 (2014), no. 3, 199–201.
- MCCARTHY, P. J.: Introduction to Arithmetical Functions. (Universitext), Springer-Verlag, New-York Inc., 1986.
- MONTGOMERY, H.—VAUGHAN, R.: Multiplicative Number Theory: I. Classical Theory. Cambridge Stud. Adv. Math. Vol. 97, Cambridge University Press, Cambridge, 2007
- SHAPIRO, H. N.: On a theorem of Selberg and generalization, Ann. of Math. 51 1950), no. 2. 485–497.
- TITCHMARSH, E. C.: The Theory of the Riemann-Zeta function. Second Edition (Edited and with a preface by D. R. Heath-Brown.) The Clarendon Press, Oxford University Press, New York, 1986.
- WILSON, B. M.: Proofs of some formulae enunciated by Ramanujan, Proc. London Math. Soc. 21 (1923), no. 2, 235–255.