Abstract
The odd-ballooning of a graph F is the graph obtained from F by replacing each edge in F by an odd cycle of length between 3 and \(q\ (q\ge 3)\) where the new vertices of the odd cycles are all different. Given a forbidden graph H and a positive integer n, the extremal number, ex(n, H), is the maximum number of edges in a graph on n vertices that does not contain H as a subgraph. Erdös et al. and Hou et al. determined the extremal number of odd-ballooning of stars. Liu and Glebov determined the extremal number of odd-ballooning of paths and cycles respectively when replacing each edge of the paths or the cycles by a triangle. In this paper we determine the extremal number and find the extremal graphs for odd-ballooning of paths and cycles, when replacing each edge of the paths or the cycles by an odd cycle of length between 3 and \(q \ (q \ge 3)\) and n is sufficiently large.








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Research was partially supported by NSFC (11871329, 11971298).
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Zhu, H., Kang, L. & Shan, E. Extremal Graphs for Odd-Ballooning of Paths and Cycles. Graphs and Combinatorics 36, 755–766 (2020). https://doi.org/10.1007/s00373-020-02150-3
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DOI: https://doi.org/10.1007/s00373-020-02150-3