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A simple and elementary proof of Whitney's unique embedding theorem
In this note we give a short and elementary proof of a more general version
of Whitney's theorem that 3-connected planar graphs have a unique embedding in
the plane. A consequence of the theorem is that cubic plane graphs cannot be
embedded in a higher genus with a simple dual. The aim of this paper is to
promote a simple and elementary proof, which is especially well suited for
lectures presenting Whitney's theorem
The Generation of Fullerenes
We describe an efficient new algorithm for the generation of fullerenes. Our
implementation of this algorithm is more than 3.5 times faster than the
previously fastest generator for fullerenes -- fullgen -- and the first program
since fullgen to be useful for more than 100 vertices. We also note a
programming error in fullgen that caused problems for 136 or more vertices. We
tabulate the numbers of fullerenes and IPR fullerenes up to 400 vertices. We
also check up to 316 vertices a conjecture of Barnette that cubic planar graphs
with maximum face size 6 are hamiltonian and verify that the smallest
counterexample to the spiral conjecture has 380 vertices.Comment: 21 pages; added a not
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