Number theory and beyond https://validator.w3.org/feed/docs/rss2.html Jensen’s inequality Bounds for divisor and Euler’s totient function Bounds for the Riemann zeta function in the critical strip Absence of zeros of $\zeta(s)$ on the line $\sigma = 1$ under prime number theorem Landau’s theorem on Dirichlet series Integral representation of Dirichlet series and Kronecker’s lemma Euler’s totient function Möbius function Lifting of units and Menon’s identity A Möbius function formulation of prime number theorem Dirichlet product and multiplicative functions Problems about Ramanujan’s sum Chebyshev functions Dirichlet series Abel’s summation by parts formula Little Picard theorem Notes Research Homotopy version of Cauchy’s theorem