The $K_{n+5}$ and $K_{3^2,1^n}$ families are obstructions to $n$-apex

Abstract

We give evidence in support of a conjecture that the $\nabla$Y$\nabla$ families of $K_{n+5}$ and $K_{3^2,1^n}$ are obstructions for the $n$-apex property.

21 pages, 3 figures, 10 tables, submitted to Contemporary Mathematics

References in corpus (1)

• Graphs on 21 edges that are not 2--apex