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A022491 An upper bound for linearized chord diagrams. 0
0, 1, 2, 6, 18, 72, 321, 1680, 9852, 64168, 457659, 3543785, 29578097, 264623046, 2525897073, 25622275565, 275257714175, 3122190896616, 37290114445901, 467812869356846 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..20.

A. Stoimenow, Enumeration of chord diagrams and an upper bound for Vassiliev invariants, J. Knot Theory Ramifications, 7 (1998), no. 1, 93-114. [broken link], [DOI]

CROSSREFS

Sequence in context: A261994 A177472 A194088 * A004395 A277862 A213427

Adjacent sequences:  A022488 A022489 A022490 * A022492 A022493 A022494

KEYWORD

nonn

AUTHOR

Alexander Stoimenow (stoimeno(AT)math.toronto.edu)

STATUS

approved

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Last modified December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)