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A338724

Number of matchings avoiding a certain pattern (see Cervetti-Ferrari, Cor. 3.1(i)).

1

1, 3, 15, 104, 910, 9503, 114317, 1547124, 23169162, 379308106

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

Matteo Cervetti and Luca Ferrari, Pattern avoidance in the matching pattern poset, arXiv:2009.01024 [math.CO], 2020.

Matteo Cervetti and Luca Ferrari, Enumeration of Some Classes of Pattern Avoiding Matchings, with a Glimpse into the Matching Pattern Poset, Annals of Combinatorics (2022).

CROSSREFS

Sequence in context: A139766 A003276 A136092 * A273197 A255427 A181131

Adjacent sequences: A338721 A338722 A338723 * A338725 A338726 A338727

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Nov 30 2020

STATUS

approved