• Corpus ID: 239009790

Walks avoiding a quadrant and the reflection principle

@inproceedings{BousquetMelou2021WalksAA,
  title={Walks avoiding a quadrant and the reflection principle},
  author={Mireille Bousquet-M'elou and Michael Wallner},
  year={2021}
}
We continue the enumeration of plane lattice walks with small steps avoiding the negative quadrant, initiated by the first author in 2016. We solve in detail a new case, namely the king model where all eight nearest neighbour steps are allowed. The associated generating function is proved to be the sum of a simple, explicit D-finite series (related to the number of walks confined to the first quadrant), and an algebraic one. This was already the case for the two models solved by the first… 

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