Highly Influenced

Rooted planar maps of various types, including all rooted planar maps, were counted by Tutte [4]. The problem of enumerating a set of unrooted planar maps ~3s the subject of [7]. In such an enumeration, two maps MI and I&, which are regarcicd as lying on a 2-sphere, are identified whenever there is a homeomorphism of the 2-sphere onto itself which maps MI… (More)

@article{Wormald1981CountingUP,
title={Counting unrooted planar maps},
author={Nicholas C. Wormald},
journal={Discrete Mathematics},
year={1981},
volume={36},
pages={205-225}
}