EN
We prove the existence of an effectively computable integer polynomial P(x,t₀,...,t₅) having the following property. Every continuous function $f: ℝ^{s} → ℝ$ can be approximated with arbitrary accuracy by an infinite sum
$∑_{r=1}^{∞} H_{r}(x₁,...,x_{s}) ∈ C^{∞}(ℝ^{s})$
of analytic functions $H_{r}$, each solving the same system of universal partial differential equations, namely
$P(x_{σ};H_r,∂H_{r}/∂x_{σ},...,∂⁵H_{r}/∂x⁵_{σ}⁵) = 0$ (σ = 1,..., s).