There was a paper about an agent simulation in Nature or Science about 20 years ago. A large number of agents are assigned random amounts of wealth. They intera

There was a paper about an agent simulation in Nature or Science about 20 years ago. A large number of agents are assigned random amounts of wealth. They interact randomly one-on-one. In the interaction, on average, the wealthier agent gets some of the wealth of the poorer one. After a long simulation, all the wealth is concentrated to two agents, and after further simulation to one. Couldn't find the paper anymore.