A complete accounting of nearby objects-from the highest-mass white dwarf progenitors down to low-mass brown dwarfs-is now possible, thanks to an almost complete set of trigonometric parallax determinations from Gaia, ground-based surveys, and Spitzer follow-up. We create a census of objects within a Sun-centered sphere of 20pc radius and check published literature to decompose each binary or higher-order system into its separate components. The result is a volume-limited census of ~3600 individual star formation products useful in measuring the initial mass function across the stellar (<8M_{sun}_) and substellar (>~5M_Jup_) regimes. Comparing our resulting initial mass function to previous measurements shows good agreement above 0.8M_{sun}_ and a divergence at lower masses. Our 20pc space densities are best fit with a quadripartite power law, {xi}(M)=dN/dM{propto}M^-{alpha}^, with long-established values of {alpha}=2.3 at high masses (0.55<M<8.00M_{sun}_), and {alpha}=1.3 at intermediate masses (0.22<M<0.55M_{sun}_), but at lower masses, we find {alpha}=0.25 for 0.05<M<0.22M_{sun}_, and {alpha}=0.6 for 0.01<M<0.05M_{sun}_. This implies that the rate of production as a function of decreasing mass diminishes in the low-mass star/high-mass brown dwarf regime before increasing again in the low-mass brown dwarf regime. Correcting for completeness, we find a star to brown dwarf number ratio of, currently, 4:1, and an average mass per object of 0.41M_{sun}_.