Abstract
Let t, k, d be integers with \(1 \le d \le k - 1\) and \(t \ge 8d + 11\), and let \(n = k(t+1)\). We show that if G is a graph of order n such that \(\delta (G) \ge d\) and \(|E(G)| \ge \left( {\begin{array}{c}n\\ 2\end{array}}\right) - (d + 1)n + dt + \frac{1}{2}(d^{2} + 3d + 4)\), then G has a \(K_{1, t}\)-factor. We also give a construction showing the sharpness of the condition on |E(G)|.




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Funding was supported by Japan Society for the Promotion of Science (17K05347, 20K03720, 19K03603).
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Shuya Chiba was supported by JSPS KAKENHI Grant numbers 17K05347, 20K03720. Shinya Fujita was supported by JSPS KAKENHI Grant number 19K03603.
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Chiba, S., Egawa, Y. & Fujita, S. Minimum Number of Edges Guaranteeing the Existence of a \(K_{1, t}\)-Factor in a Graph. Graphs and Combinatorics 39, 27 (2023). https://doi.org/10.1007/s00373-023-02616-0
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DOI: https://doi.org/10.1007/s00373-023-02616-0