Identifier
Values
[] => [] => [1,0] => [(1,2)] => 1
[[]] => [1,0] => [1,1,0,0] => [(1,4),(2,3)] => 2
[[],[]] => [1,0,1,0] => [1,1,0,1,0,0] => [(1,6),(2,3),(4,5)] => 2
[[[]]] => [1,1,0,0] => [1,1,1,0,0,0] => [(1,6),(2,5),(3,4)] => 3
[[],[],[]] => [1,0,1,0,1,0] => [1,1,0,1,0,1,0,0] => [(1,8),(2,3),(4,5),(6,7)] => 2
[[],[[]]] => [1,0,1,1,0,0] => [1,1,0,1,1,0,0,0] => [(1,8),(2,3),(4,7),(5,6)] => 3
[[[]],[]] => [1,1,0,0,1,0] => [1,1,1,0,0,1,0,0] => [(1,8),(2,5),(3,4),(6,7)] => 3
[[[],[]]] => [1,1,0,1,0,0] => [1,1,1,0,1,0,0,0] => [(1,8),(2,7),(3,4),(5,6)] => 3
[[[[]]]] => [1,1,1,0,0,0] => [1,1,1,1,0,0,0,0] => [(1,8),(2,7),(3,6),(4,5)] => 4
[[],[],[],[]] => [1,0,1,0,1,0,1,0] => [1,1,0,1,0,1,0,1,0,0] => [(1,10),(2,3),(4,5),(6,7),(8,9)] => 2
[[],[],[[]]] => [1,0,1,0,1,1,0,0] => [1,1,0,1,0,1,1,0,0,0] => [(1,10),(2,3),(4,5),(6,9),(7,8)] => 3
[[],[[]],[]] => [1,0,1,1,0,0,1,0] => [1,1,0,1,1,0,0,1,0,0] => [(1,10),(2,3),(4,7),(5,6),(8,9)] => 3
[[],[[],[]]] => [1,0,1,1,0,1,0,0] => [1,1,0,1,1,0,1,0,0,0] => [(1,10),(2,3),(4,9),(5,6),(7,8)] => 3
[[],[[[]]]] => [1,0,1,1,1,0,0,0] => [1,1,0,1,1,1,0,0,0,0] => [(1,10),(2,3),(4,9),(5,8),(6,7)] => 4
[[[]],[],[]] => [1,1,0,0,1,0,1,0] => [1,1,1,0,0,1,0,1,0,0] => [(1,10),(2,5),(3,4),(6,7),(8,9)] => 3
[[[]],[[]]] => [1,1,0,0,1,1,0,0] => [1,1,1,0,0,1,1,0,0,0] => [(1,10),(2,5),(3,4),(6,9),(7,8)] => 3
[[[],[]],[]] => [1,1,0,1,0,0,1,0] => [1,1,1,0,1,0,0,1,0,0] => [(1,10),(2,7),(3,4),(5,6),(8,9)] => 3
[[[[]]],[]] => [1,1,1,0,0,0,1,0] => [1,1,1,1,0,0,0,1,0,0] => [(1,10),(2,7),(3,6),(4,5),(8,9)] => 4
[[[],[],[]]] => [1,1,0,1,0,1,0,0] => [1,1,1,0,1,0,1,0,0,0] => [(1,10),(2,9),(3,4),(5,6),(7,8)] => 3
[[[],[[]]]] => [1,1,0,1,1,0,0,0] => [1,1,1,0,1,1,0,0,0,0] => [(1,10),(2,9),(3,4),(5,8),(6,7)] => 4
[[[[]],[]]] => [1,1,1,0,0,1,0,0] => [1,1,1,1,0,0,1,0,0,0] => [(1,10),(2,9),(3,6),(4,5),(7,8)] => 4
[[[[],[]]]] => [1,1,1,0,1,0,0,0] => [1,1,1,1,0,1,0,0,0,0] => [(1,10),(2,9),(3,8),(4,5),(6,7)] => 4
[[[[[]]]]] => [1,1,1,1,0,0,0,0] => [1,1,1,1,1,0,0,0,0,0] => [(1,10),(2,9),(3,8),(4,7),(5,6)] => 5
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Description
The nesting number of a perfect matching.
This is the maximal number of chords in the standard representation of a perfect matching that mutually nest.
Map
prime Dyck path
Description
Return the Dyck path obtained by adding an initial up and a final down step.
Map
to Dyck path
Description
Return the Dyck path of the corresponding ordered tree induced by the recurrence of the Catalan numbers, see wikipedia:Catalan_number.
This sends the maximal height of the Dyck path to the depth of the tree.
Map
to tunnel matching
Description
Sends a Dyck path of semilength n to the noncrossing perfect matching given by matching an up-step with the corresponding down-step.
This is, for a Dyck path $D$ of semilength $n$, the perfect matching of $\{1,\dots,2n\}$ with $i < j$ being matched if $D_i$ is an up-step and $D_j$ is the down-step connected to $D_i$ by a tunnel.