The number of connected sparsely edged graphs. II. Smooth graphs and blocks
- 1 December 1978
- journal article
- research article
- Published by Wiley in Journal of Graph Theory
- Vol. 2 (4) , 299-305
- https://doi.org/10.1002/jgt.3190020403
Abstract
A smooth graph is a connected graph without endpoints; f(n, q) is the number of connected graphs, v(n, q) is the number of smooth graphs, and u(n, q) is the number of blocks on n labeled points and q edges: Wk, Vk, and Uk are the exponential generating functions of f(n, n + k), v(n, n + k), and u(n, n + k), respectively. For any k ⩾ 1, our reduction method shows that Vk can be deduced at once from Wk, which was found for successive k by the computer method described in our previous paper. Again the reduction method shows that Uk must be a sum of powers (mostly negative) of 1 ‐ X and, given this information, we develop a recurrence method well suited to calculate Uk for successive k. Exact formulas for v(n, n + k) and u(n, n + k) for general n follow at once.Keywords
This publication has 3 references indexed in Scilit:
- The number of connected sparsely edged graphsJournal of Graph Theory, 1977
- On the Enumeration of Mayer Cluster IntegralsProceedings of the Physical Society, 1958
- On the Theory of the Virial Development of the Equation of State of Monoatomic GasesThe Journal of Chemical Physics, 1953