Minimum Level Nonplanar Patterns for Trees

Minimum level nonplanar (MLNP) patterns play the role for level planar graphs that the forbidden Kuratowksi subdivisions K5 and K3,3 play for planar graphs. We add two MLNP patterns for trees to the previous set of tree patterns given by Healy et al. Neither of these patterns match any of the previous patterns. We show that this new set of patterns completely characterizes level planar trees.

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