We study competing-prover one-round interactive proof systems. We show that one-round proof systems in which the rst prover is trying to convince a veri er to accept and the second prover is trying to make the veri er reject recognize languages in NEXPTIME, and, with restrictions on communication and randomness, languages in NP. We extended the restricted model to an alternating sequence of k competing provers, which we show characterizes P
Marcos A. Kiwi, Carsten Lund, Alexander Russell, D