# isAntichain -- determines if a given list of vertices is an antichain of a poset

## Synopsis

• Usage:
i = isAntichain(P, L)
• Inputs:
• P, an instance of the type Poset,
• L, a list, containing elements of $P$
• Outputs:
• i, , whether $L$ is an antichain of $P$

## Description

A set of elements of $P$ is called an antichain if no two distinct elements of the set are comparable.

 i1 : D = divisorPoset 12; i2 : isAntichain(D, {2,3}) o2 = true i3 : isAntichain(D, {2,6}) o3 = false