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Your data matches 1 statistic following compositions of up to 3 maps.
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Matching statistic: St001909
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Values
([],1)
=> 2
([],2)
=> 4
([(0,1)],2)
=> 4
([],3)
=> 8
([(1,2)],3)
=> 8
([(0,1),(0,2)],3)
=> 8
([(0,2),(2,1)],3)
=> 7
([(0,2),(1,2)],3)
=> 8
([],4)
=> 16
([(2,3)],4)
=> 16
([(1,2),(1,3)],4)
=> 16
([(0,1),(0,2),(0,3)],4)
=> 16
([(0,2),(0,3),(3,1)],4)
=> 14
([(0,1),(0,2),(1,3),(2,3)],4)
=> 13
([(1,2),(2,3)],4)
=> 14
([(0,3),(3,1),(3,2)],4)
=> 13
([(1,3),(2,3)],4)
=> 16
([(0,3),(1,3),(3,2)],4)
=> 13
([(0,3),(1,3),(2,3)],4)
=> 16
([(0,3),(1,2)],4)
=> 16
([(0,3),(1,2),(1,3)],4)
=> 16
([(0,2),(0,3),(1,2),(1,3)],4)
=> 16
([(0,3),(2,1),(3,2)],4)
=> 11
([(0,3),(1,2),(2,3)],4)
=> 14
([],5)
=> 32
([(3,4)],5)
=> 32
([(2,3),(2,4)],5)
=> 32
([(1,2),(1,3),(1,4)],5)
=> 32
([(0,1),(0,2),(0,3),(0,4)],5)
=> 32
([(0,2),(0,3),(0,4),(4,1)],5)
=> 28
([(0,1),(0,2),(0,3),(2,4),(3,4)],5)
=> 26
([(0,1),(0,2),(0,3),(1,4),(2,4),(3,4)],5)
=> 25
([(1,3),(1,4),(4,2)],5)
=> 28
([(0,3),(0,4),(4,1),(4,2)],5)
=> 26
([(1,2),(1,3),(2,4),(3,4)],5)
=> 26
([(0,2),(0,3),(2,4),(3,4),(4,1)],5)
=> 19
([(0,3),(0,4),(3,2),(4,1)],5)
=> 25
([(0,2),(0,3),(2,4),(3,1),(3,4)],5)
=> 24
([(0,1),(0,2),(1,3),(1,4),(2,3),(2,4)],5)
=> 23
([(2,3),(3,4)],5)
=> 28
([(1,4),(4,2),(4,3)],5)
=> 26
([(0,4),(4,1),(4,2),(4,3)],5)
=> 25
([(2,4),(3,4)],5)
=> 32
([(1,4),(2,4),(4,3)],5)
=> 26
([(0,4),(1,4),(4,2),(4,3)],5)
=> 23
([(1,4),(2,4),(3,4)],5)
=> 32
([(0,4),(1,4),(2,4),(4,3)],5)
=> 25
([(0,4),(1,4),(2,4),(3,4)],5)
=> 32
([(0,4),(1,4),(2,3)],5)
=> 32
([(0,4),(1,3),(2,3),(2,4)],5)
=> 32
Description
The number of interval-closed sets of a poset.
For a poset $P$ and a subset $I$ of $P$, we say that $I$ is an ''interval-closed'' set if for all $x, y \in I$ such that $x \leq y$, then $z \in I$ if $x \leq z \leq y$.
There is a bijection between interval-closed sets of a poset $P$ and pairs of disjoint antichains $(A, B)$ of $P$ such that any element in $B$ is in the order ideal $\Delta(A)$ generated by $A$. (Proposition 2.5 of [1]).
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