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arXiv · 2412.07873

Lucky cars and lucky spots in parking functions

Steve Butler·Kimberly Hadaway·Victoria Lenius·Preston Martens·Marshall Moats
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Abstract

Parking functions correspond with preferences of $n$ cars which enter sequentially to park on a one-way street where (1) each car parks in the first available spot greater than or equal to its preference and (2) all cars successfully park. When a car parks in its preferred spot then the corresponding car and corresponding spot are deemed ``lucky.'' This paper looks briefly at lucky cars which have previously been studied and in simple cases can be understood by a generalization of a result due to Pollak. We also consider lucky spots where the situation is more complex and not previously studied. Probabilities and asymptotics for lucky spots are given for the first few spots on the one-way street. We close with an exploration of the special cases when cars enter the one-way street in either weakly-increasing or weakly-decreasing order of their preferences.

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Steve Butler, Kimberly Hadaway, Victoria Lenius, Preston Martens, Marshall Moats. 2024-12-10. Lucky cars and lucky spots in parking functions. https://arxiv.org/abs/2412.07873

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