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A278993
Number of simple chord diagrams with n chords, up to rotation.
3
0, 1, 1, 4, 21, 176, 1893, 25030, 382272, 6604535, 127222636, 2702798537, 62778105236, 1582725739329, 43046433007765, 1256332883208474, 39165907107963273, 1298945495674093932, 45666536827274985585, 1696460750775267473762
OFFSET
1,4
LINKS
E. Krasko and A. Omelchenko, Enumeration of Chord Diagrams without Loops and Parallel Chords, arXiv preprint arXiv:1601.05073 [math.CO], 2016.
E. Krasko and A. Omelchenko, Enumeration of Chord Diagrams without Loops and Parallel Chords, The Electronic Journal of Combinatorics, 24(3) (2017), #P3.43.
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 07 2016
STATUS
approved