From a single axiom — Eₑx + Eᵤnex = mc² = constant — follows a sharp limit on the atomic number. When the exposed energy equals the reserve, the velocity of the 1s electron reaches (√3/2) ·c ≈ 0. 866c; beyond it no reserve remains to hold the structure. Since v₁s = Z·α·c, the existence condition is Z·α < √3/2, that is Z < 118. 68. Oganesson (Z = 118, v₁s = 0. 861c) lies just below the limit and therefore exists but lives very briefly; element 119 (v₁s = 0. 868c) exceeds it and does not form as an atom. The same limit — seven levels, one hundred and eighteen elements — follows from five independent routes: kinematic, harmonic, logarithmic, from the capacities, and topological. The prediction is binary and falsifiable: a single nucleus of element 119 with the signature of a formed atom refutes the entire framework.
Shpetim Nazarko (Wed,) studied this question.