On Conway's thrackle conjecture

被引:40
作者
Lovasz, L
Pach, J
Szegedy, M
机构
[1] CUNY CITY COLL,DEPT COMP SCI,NEW YORK,NY 10012
[2] NYU,COURANT INST,NEW YORK,NY 10012
[3] AT&T BELL LABS,MATH SCI RES CTR,MURRAY HILL,NJ 07974
关键词
Related Problem; Point Interior; Common Vertex;
D O I
10.1007/PL00009322
中图分类号
TP301 [理论、方法];
学科分类号
081202 ;
摘要
A thrackle is a graph drawn in the plane so that its edges are represented by Jordan arcs and any two distinct arcs either meet at exactly one common vertex or cross at exactly one point interior to both arcs. About 40 years ago, J. H. Conway conjectured that the number of edges of a thrackle cannot exceed the number of its vertices. We show that a thrackle has at most twice as many edges as vertices. Some related problems and generalizations are also considered.
引用
收藏
页码:369 / 376
页数:8
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