Resolution of the Black-Hole Central Singularity in a Single Nonlinear Field Equation

This research note presents a concise mathematical proof showing that a single conservative nonlinear field equation admits stationary, spherically symmetric solutions that are regular at the center, possess a well-defined horizon, and reproduce Schwarzschild asymptotics at large radii.
The result demonstrates that the classical black-hole singularity can be removed within a single closed formalism, without external corrections or additional fields.
All parameters and symbols are presented generically for confidentiality.
The study was conducted independently by Eurian Barros (Independent Researcher).