> Then, one card at a time is repeatedly moved from the bottom of one of the packets to the top of the shuffled deck, such that if x cards remain in one packet

> Then, one card at a time is repeatedly moved from the bottom of one of the packets to the top of the shuffled deck, such that if x cards remain in one packet and y cards remain in the other packet, then the probability of choosing a card from the first packet is x/(x + y) and the probability of choosing a card from the second packet is y/(x + y). https://en.wikipedia.org/wiki/Gilbert%E2%80%93Shannon%E2%80%93Reeds_model https://en.wikipedia.org/wiki/Gilbert%E2%80%93Shannon%E2%80%...