If a sequence of experiments or trials T₁, T₂, T₃, …, T_k could result, respectively, in n₁, n₂ n₃, …, n_k possible outcomes, and the numbers n₁, n₂ n₃, …, n_k do not depend on which outcomes actually occurred, the entire sequence of k experiments has n₁× n₂ × n₃× …× n_k possible outcomes.