# Planar Tur\'an Number of Double Stars

@inproceedings{Ghosh2021PlanarTN, title={Planar Tur\'an Number of Double Stars}, author={Debarun Ghosh and Ervin GyHori and Addisu Paulos and Chuanqi Xiao}, year={2021} }

Given a graph F , the planar Turán number of F , denoted exP(n, F ), is the maximum number of edges in an n-vertex F -free planar graph. Such an extremal graph problem was initiated by Dowden while determining sharp upper bound for exP(n,C4) and exP(n,C5), where C4 and C5 are cycles of length four and five respectively. In this paper we determined an upper bound for exP(n, S2,2), exP(n, S2,3), exP(n, S2,4), exP(n, S2,5), exP(n, S3,3) and exP(n, S3,4), where Sm,n is a double star with m and n…

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