摘要
Some researchers have proved that Adam＇s conjecture is wrong. However, under special conditions,it is right. Let Zn be a cyclic group of order n and Cn（S） be the circulant digraph of Zn with respect to S？Zn／{0}. In the literature, some people have used a spectral method to solve the isomorphism for the circulants of prime-power order. In this paper, we also use the spectral method to characterize the circulants of order paqbωc（where p,q and ω are all distinct primes）, and to make Adam＇s conjecture right.
Some researchers have proved that Adam＇s conjecture is wrong. However, under special conditions,it is right. Let Zn be a cyclic group of order n and Cn（S） be the circulant digraph of Zn with respect to S？Zn／{0}. In the literature, some people have used a spectral method to solve the isomorphism for the circulants of prime-power order. In this paper, we also use the spectral method to characterize the circulants of order paqbωc（where p,q and ω are all distinct primes）, and to make Adam＇s conjecture right.
基金
supported by Start high-level personnel of scientific research funds of Jiangsu Second Normal University(No.918001)
NSFC(11171283)
