[en] E.g.f.: x/(x+3-2*exp(x)). [en] Number of associative and quasitrivial binary operations on {1,...,n} that have neutral elements. Also: Number of associative and quasitrivial binary operations on {1,...,n} that have annihilator elements.
Disciplines :
Mathématiques Sciences informatiques
Auteur, co-auteur :
MARICHAL, Jean-Luc ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Mathematics Research Unit
