Follow
On endomorphisms of the bicyclic semigroup and the extended bicyclic semigroup. (arXiv:2202.00073v1 [math.GR]) http://arxiv.org/abs/2202.00073
On endomorphisms of the bicyclic semigroup and the extended bicyclic semigroup. (arXiv:2202.00073v1 [math.GR]) http://arxiv.org/abs/2202.00073