Number of paths between grid corners, allowing diagonal steps
Delannoy number
Named after
Henri–Auguste Delannoy
No. of known terms
infinity
Formula
OEIS index
A008288
Square array of Delannoy
In mathematics, a Delannoy number counts the paths from the southwest corner (0, 0) of a rectangular grid to the northeast corner (m, n), using only single steps north, northeast, or east. The Delannoy numbers are named after French army officer and amateur mathematician Henri Delannoy.[1]
The Delannoy number also counts the global alignments of two sequences of lengths and ,[2] the points in an m-dimensional integer lattice or cross polytope which are at most n steps from the origin,[3] and, in cellular automata, the cells in an m-dimensional von Neumann neighborhood of radius n.[4]
^Covington, Michael A. (2004), "The number of distinct alignments of two strings", Journal of Quantitative Linguistics, 11 (3): 173–182, doi:10.1080/0929617042000314921, S2CID 40549706
^Luther, Sebastian; Mertens, Stephan (2011), "Counting lattice animals in high dimensions", Journal of Statistical Mechanics: Theory and Experiment, 2011 (9): P09026, arXiv:1106.1078, Bibcode:2011JSMTE..09..026L, doi:10.1088/1742-5468/2011/09/P09026, S2CID 119308823
^Breukelaar, R.; Bäck, Th. (2005), "Using a Genetic Algorithm to Evolve Behavior in Multi Dimensional Cellular Automata: Emergence of Behavior", Proceedings of the 7th Annual Conference on Genetic and Evolutionary Computation (GECCO '05), New York, NY, USA: ACM, pp. 107–114, doi:10.1145/1068009.1068024, ISBN 1-59593-010-8, S2CID 207157009
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