Convergence, Probability, Cumulative Distribution, Statistics, Editors Pick.
The bias on the k-th coin can be represented by the Probability Mass Function of X_k as follows: PMF of X_k for k ϵ [1, ∞] (Image by Author) Its easy to verify that P(X_k=0) + P(X_k = 1) = 1. So the design our PMF is sound. You may also want to verify when k = 1, the term (1 — 1/k) = 0, so P(X_k=0)