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Chromatic Sums for Rooted Planar Triangulations, IV: The Case λ = ∞

Published online by Cambridge University Press:  20 November 2018

W. T. Tutte*
Affiliation:
University of Waterloo, Waterloo, Ontario
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Summary

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The chromial P(M, λ) of a planar near-triangulation M has the leading term λv(M), where v(M) is the number of vertices of M. The problem of finding the number of rooted planar near-triangulations of a given class S, all supposed to have the same number of vertices, can be regarded as a special case of the problem of finding chromatic sums. We can sum P(M, λ) over the members of S, divide by the appropriate power of λ and let λ → ∞. We thus get the sum of the coefficient of the leading term of P(M, λ) for all MS, that is we get the number of members of S.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1973

References

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