The skewness of a graph G is the minimum number of edges in G whose removal results in a planar graph. In this paper, we show that the skewness of the generalized Petersen graph P (3k, k) is $\lceil\frac{k}{2}+1\rceil$, where k ≥ 4. As a byproduct, it is shown that for k ≥ 4, $\lceil\frac{k}{2}+1\rceil \leq cr(P(3k,k)) \leq k$, where cr (G) denotes the crossing number of G.
['Gek L. Chia', 'Chan Lye Lee']
Crossing numbers and skewness of some generalized petersen graphs