In mathematics, the harmonic series is the infinite series formed by summing all positive unit fractions: The first n {\displaystyle n} terms of the series sum to approximately ln ⁡ n + γ {\displaystyle \ln n+\gamma }, where ln {\displaystyle \ln } is the natural logarithm and γ ≈ 0.577 {\displaystyle \gamma \approx 0.577} is the Euler–Mascheroni constant. Wikipedia