Deveci, Sinan (2022). "On a Double Series Representation of the Natural Logarithm, the Asymptotic Behavior of Hölder Means, and an Elementary Estimate for the Prime Counting Function". arXiv:2211.10751 [math.NT]. See Theorem 5.2. on pages 22 - 23
Harremoës, Peter (2011). "Is Zero a Natural Number?". arXiv:1102.0418 [math.HO]. A synopsis on the nature of 0 which frames the choice of minimum as the dichotomy between ordinals and cardinals.
Khristo N. Boyadzhiev (2022). "New series identities with Cauchy, Stirling, and harmonic numbers, and Laguerre polynomials". pp. 2, 6. arXiv:1911.00186 [math.NT].
Kifowit, Steven J. (2019). More Proofs of Divergence of the Harmonic Series(PDF) (Report). Prairie State College. Retrieved 2024-04-24. See Proofs 23 and 24 for details on the relationship between harmonic numbers and logarithmic functions.