Rivest-Vuillemin Conjecture Is True for Monotone Boolean Functions with Twelve Variables

A Boolean function f(x1, x2, …, xn) is elusive if every decision tree computing f must examine all n variables in the worst case. It is a long-standing conjecture that every non-trivial monotone weakly symmetric Boolean function is elusive. In this paper, we prove this conjecture for Boolean functions with twelve variables