International Journal of Mathematics and Mathematical Sciences
Volume 31 (2002), Issue 12, Pages 725-729

A note on operators of deletion and contraction for antichains

Andrey O. Matveev

Data Center Company, Box 5, Ekaterinburg 620034, Russia

Received 16 August 2001; Revised 28 March 2002

Copyright © 2002 Andrey O. Matveev. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The operators of deletion and contraction for clutters are generalized to those for antichains of finite bounded posets. A generalization of the result by Seymour (1976), describing the relationship between the operators of deletion, contraction, and the blocker map, is considered as a comparison in the lattice of antichains of a poset.