Non-regular unary language and parallel communicating Watson-Crick automata systems

In 2006, Czeizler et al. introduced parallel communicating Watson-Crick automata system. They showed that parallel communicating Watson-Crick automata system can accept the non-regular unary language L={an2, where n>1} using non-injective complementarity relation and three components. In this paper, we improve on Czeizler et al.'s work by showing that parallel communicating Watson-Crick automata system can accept the same language L using just two components.