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Your data matches 15 different statistics following compositions of up to 3 maps.
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Matching statistic: St000662
Mp00055: Parking functions to labelling permutationPermutations
St000662: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => 0
[1,1] => [1,2] => 0
[1,2] => [1,2] => 0
[2,1] => [2,1] => 1
[1,1,1] => [1,2,3] => 0
[1,1,2] => [1,2,3] => 0
[1,2,1] => [1,3,2] => 1
[2,1,1] => [2,3,1] => 1
[1,1,3] => [1,2,3] => 0
[1,3,1] => [1,3,2] => 1
[3,1,1] => [2,3,1] => 1
[1,2,2] => [1,2,3] => 0
[2,1,2] => [2,1,3] => 1
[2,2,1] => [3,1,2] => 1
[1,2,3] => [1,2,3] => 0
[1,3,2] => [1,3,2] => 1
[2,1,3] => [2,1,3] => 1
[2,3,1] => [3,1,2] => 1
[3,1,2] => [2,3,1] => 1
[3,2,1] => [3,2,1] => 2
[1,1,1,1] => [1,2,3,4] => 0
[1,1,1,2] => [1,2,3,4] => 0
[1,1,2,1] => [1,2,4,3] => 1
[1,2,1,1] => [1,3,4,2] => 1
[2,1,1,1] => [2,3,4,1] => 1
[1,1,1,3] => [1,2,3,4] => 0
[1,1,3,1] => [1,2,4,3] => 1
[1,3,1,1] => [1,3,4,2] => 1
[3,1,1,1] => [2,3,4,1] => 1
[1,1,1,4] => [1,2,3,4] => 0
[1,1,4,1] => [1,2,4,3] => 1
[1,4,1,1] => [1,3,4,2] => 1
[4,1,1,1] => [2,3,4,1] => 1
[1,1,2,2] => [1,2,3,4] => 0
[1,2,1,2] => [1,3,2,4] => 1
[1,2,2,1] => [1,4,2,3] => 1
[2,1,1,2] => [2,3,1,4] => 1
[2,1,2,1] => [2,4,1,3] => 1
[2,2,1,1] => [3,4,1,2] => 2
[1,1,2,3] => [1,2,3,4] => 0
[1,1,3,2] => [1,2,4,3] => 1
[1,2,1,3] => [1,3,2,4] => 1
[1,2,3,1] => [1,4,2,3] => 1
[1,3,1,2] => [1,3,4,2] => 1
[1,3,2,1] => [1,4,3,2] => 2
[2,1,1,3] => [2,3,1,4] => 1
[2,1,3,1] => [2,4,1,3] => 1
[2,3,1,1] => [3,4,1,2] => 2
[3,1,1,2] => [2,3,4,1] => 1
[3,1,2,1] => [2,4,3,1] => 2
Description
The staircase size of the code of a permutation. The code c(π) of a permutation π of length n is given by the sequence (c1,,cn) with ci=|{j>i:π(j)<π(i)}|. This is a bijection between permutations and all sequences (c1,,cn) with 0cini. The staircase size of the code is the maximal k such that there exists a subsequence (cik,,ci1) of c(π) with cijj. This statistic is mapped through [[Mp00062]] to the number of descents, showing that together with the number of inversions [[St000018]] it is Euler-Mahonian.
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
St000021: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => 0
[1,1] => [1,2] => [1,2] => 0
[1,2] => [1,2] => [1,2] => 0
[2,1] => [2,1] => [2,1] => 1
[1,1,1] => [1,2,3] => [1,2,3] => 0
[1,1,2] => [1,2,3] => [1,2,3] => 0
[1,2,1] => [1,3,2] => [3,1,2] => 1
[2,1,1] => [2,3,1] => [1,3,2] => 1
[1,1,3] => [1,2,3] => [1,2,3] => 0
[1,3,1] => [1,3,2] => [3,1,2] => 1
[3,1,1] => [2,3,1] => [1,3,2] => 1
[1,2,2] => [1,2,3] => [1,2,3] => 0
[2,1,2] => [2,1,3] => [2,1,3] => 1
[2,2,1] => [3,1,2] => [2,3,1] => 1
[1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,2] => [1,3,2] => [3,1,2] => 1
[2,1,3] => [2,1,3] => [2,1,3] => 1
[2,3,1] => [3,1,2] => [2,3,1] => 1
[3,1,2] => [2,3,1] => [1,3,2] => 1
[3,2,1] => [3,2,1] => [3,2,1] => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => 2
Description
The number of descents of a permutation. This can be described as an occurrence of the vincular mesh pattern ([2,1], {(1,0),(1,1),(1,2)}), i.e., the middle column is shaded, see [3].
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
St000325: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => 1 = 0 + 1
[1,1] => [1,2] => [1,2] => 1 = 0 + 1
[1,2] => [1,2] => [1,2] => 1 = 0 + 1
[2,1] => [2,1] => [2,1] => 2 = 1 + 1
[1,1,1] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,1,2] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,2,1] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[2,1,1] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[1,1,3] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,3,1] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[3,1,1] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[1,2,2] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[2,1,2] => [2,1,3] => [2,1,3] => 2 = 1 + 1
[2,2,1] => [3,1,2] => [2,3,1] => 2 = 1 + 1
[1,2,3] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,3,2] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[2,1,3] => [2,1,3] => [2,1,3] => 2 = 1 + 1
[2,3,1] => [3,1,2] => [2,3,1] => 2 = 1 + 1
[3,1,2] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[3,2,1] => [3,2,1] => [3,2,1] => 3 = 2 + 1
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => 2 = 1 + 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => 2 = 1 + 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => 2 = 1 + 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => 2 = 1 + 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => 3 = 2 + 1
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => 2 = 1 + 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => 2 = 1 + 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => 3 = 2 + 1
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => 2 = 1 + 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => 2 = 1 + 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => 3 = 2 + 1
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => 3 = 2 + 1
Description
The width of the tree associated to a permutation. A permutation can be mapped to a rooted tree with vertices {0,1,2,,n} and root 0 in the following way. Entries of the permutations are inserted one after the other, each child is larger than its parent and the children are in strict order from left to right. Details of the construction are found in [1]. The width of the tree is given by the number of leaves of this tree. Note that, due to the construction of this tree, the width of the tree is always one more than the number of descents [[St000021]]. This also matches the number of runs in a permutation [[St000470]]. See also [[St000308]] for the height of this tree.
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
St000470: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => 1 = 0 + 1
[1,1] => [1,2] => [1,2] => 1 = 0 + 1
[1,2] => [1,2] => [1,2] => 1 = 0 + 1
[2,1] => [2,1] => [2,1] => 2 = 1 + 1
[1,1,1] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,1,2] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,2,1] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[2,1,1] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[1,1,3] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,3,1] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[3,1,1] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[1,2,2] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[2,1,2] => [2,1,3] => [2,1,3] => 2 = 1 + 1
[2,2,1] => [3,1,2] => [2,3,1] => 2 = 1 + 1
[1,2,3] => [1,2,3] => [1,2,3] => 1 = 0 + 1
[1,3,2] => [1,3,2] => [3,1,2] => 2 = 1 + 1
[2,1,3] => [2,1,3] => [2,1,3] => 2 = 1 + 1
[2,3,1] => [3,1,2] => [2,3,1] => 2 = 1 + 1
[3,1,2] => [2,3,1] => [1,3,2] => 2 = 1 + 1
[3,2,1] => [3,2,1] => [3,2,1] => 3 = 2 + 1
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => 2 = 1 + 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => 2 = 1 + 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => 2 = 1 + 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => 2 = 1 + 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => 3 = 2 + 1
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => 1 = 0 + 1
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => 2 = 1 + 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => 2 = 1 + 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => 2 = 1 + 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => 2 = 1 + 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => 3 = 2 + 1
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => 2 = 1 + 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => 2 = 1 + 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => 3 = 2 + 1
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => 2 = 1 + 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => 3 = 2 + 1
Description
The number of runs in a permutation. A run in a permutation is an inclusion-wise maximal increasing substring, i.e., a contiguous subsequence. This is the same as the number of descents plus 1.
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00235: Permutations descent views to invisible inversion bottomsPermutations
St000155: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => [1] => 0
[1,1] => [1,2] => [1,2] => [1,2] => 0
[1,2] => [1,2] => [1,2] => [1,2] => 0
[2,1] => [2,1] => [2,1] => [2,1] => 1
[1,1,1] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,1,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,2,1] => [1,3,2] => [3,1,2] => [3,1,2] => 1
[2,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,1,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,1] => [1,3,2] => [3,1,2] => [3,1,2] => 1
[3,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,2,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[2,1,2] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,2,1] => [3,1,2] => [2,3,1] => [3,2,1] => 1
[1,2,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,2] => [1,3,2] => [3,1,2] => [3,1,2] => 1
[2,1,3] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,3,1] => [3,1,2] => [2,3,1] => [3,2,1] => 1
[3,1,2] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[3,2,1] => [3,2,1] => [3,2,1] => [2,3,1] => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => [4,1,2,3] => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => [4,2,1,3] => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => [4,1,2,3] => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => [4,2,1,3] => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => [4,1,2,3] => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => [4,2,1,3] => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => [3,1,2,4] => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => [4,1,3,2] => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => [1,4,3,2] => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => [3,4,1,2] => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => [4,1,2,3] => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => [3,1,2,4] => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => [4,1,3,2] => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => [4,2,1,3] => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => [3,1,4,2] => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => [1,4,3,2] => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => [3,4,1,2] => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => [4,3,1,2] => 2
Description
The number of exceedances (also excedences) of a permutation. This is defined as exc(σ)=#{i:σ(i)>i}. It is known that the number of exceedances is equidistributed with the number of descents, and that the bistatistic (exc,den) is [[Permutations/Descents-Major#Euler-Mahonian_statistics|Euler-Mahonian]]. Here, den is the Denert index of a permutation, see [[St000156]].
Matching statistic: St000157
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00070: Permutations Robinson-Schensted recording tableauStandard tableaux
St000157: Standard tableaux ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => [[1]]
=> 0
[1,1] => [1,2] => [1,2] => [[1,2]]
=> 0
[1,2] => [1,2] => [1,2] => [[1,2]]
=> 0
[2,1] => [2,1] => [2,1] => [[1],[2]]
=> 1
[1,1,1] => [1,2,3] => [1,2,3] => [[1,2,3]]
=> 0
[1,1,2] => [1,2,3] => [1,2,3] => [[1,2,3]]
=> 0
[1,2,1] => [1,3,2] => [3,1,2] => [[1,3],[2]]
=> 1
[2,1,1] => [2,3,1] => [1,3,2] => [[1,2],[3]]
=> 1
[1,1,3] => [1,2,3] => [1,2,3] => [[1,2,3]]
=> 0
[1,3,1] => [1,3,2] => [3,1,2] => [[1,3],[2]]
=> 1
[3,1,1] => [2,3,1] => [1,3,2] => [[1,2],[3]]
=> 1
[1,2,2] => [1,2,3] => [1,2,3] => [[1,2,3]]
=> 0
[2,1,2] => [2,1,3] => [2,1,3] => [[1,3],[2]]
=> 1
[2,2,1] => [3,1,2] => [2,3,1] => [[1,2],[3]]
=> 1
[1,2,3] => [1,2,3] => [1,2,3] => [[1,2,3]]
=> 0
[1,3,2] => [1,3,2] => [3,1,2] => [[1,3],[2]]
=> 1
[2,1,3] => [2,1,3] => [2,1,3] => [[1,3],[2]]
=> 1
[2,3,1] => [3,1,2] => [2,3,1] => [[1,2],[3]]
=> 1
[3,1,2] => [2,3,1] => [1,3,2] => [[1,2],[3]]
=> 1
[3,2,1] => [3,2,1] => [3,2,1] => [[1],[2],[3]]
=> 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => [[1,3,4],[2]]
=> 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => [[1,2],[3,4]]
=> 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => [[1,2,3],[4]]
=> 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => [[1,3,4],[2]]
=> 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => [[1,2],[3,4]]
=> 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => [[1,2,3],[4]]
=> 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => [[1,3,4],[2]]
=> 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => [[1,2],[3,4]]
=> 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => [[1,2,3],[4]]
=> 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => [[1,3,4],[2]]
=> 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => [[1,2],[3,4]]
=> 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => [[1,2,4],[3]]
=> 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => [[1,2,3],[4]]
=> 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => [[1,3],[2,4]]
=> 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => [[1,2,3,4]]
=> 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => [[1,3,4],[2]]
=> 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => [[1,3,4],[2]]
=> 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => [[1,2],[3,4]]
=> 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => [[1,2],[3,4]]
=> 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => [[1,4],[2],[3]]
=> 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => [[1,2,4],[3]]
=> 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => [[1,2,3],[4]]
=> 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => [[1,3],[2,4]]
=> 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => [[1,2,3],[4]]
=> 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => [[1,3],[2],[4]]
=> 2
Description
The number of descents of a standard tableau. Entry i of a standard Young tableau is a descent if i+1 appears in a row below the row of i.
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00064: Permutations reversePermutations
St000245: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => [1] => 0
[1,1] => [1,2] => [1,2] => [2,1] => 0
[1,2] => [1,2] => [1,2] => [2,1] => 0
[2,1] => [2,1] => [2,1] => [1,2] => 1
[1,1,1] => [1,2,3] => [1,2,3] => [3,2,1] => 0
[1,1,2] => [1,2,3] => [1,2,3] => [3,2,1] => 0
[1,2,1] => [1,3,2] => [3,1,2] => [2,1,3] => 1
[2,1,1] => [2,3,1] => [1,3,2] => [2,3,1] => 1
[1,1,3] => [1,2,3] => [1,2,3] => [3,2,1] => 0
[1,3,1] => [1,3,2] => [3,1,2] => [2,1,3] => 1
[3,1,1] => [2,3,1] => [1,3,2] => [2,3,1] => 1
[1,2,2] => [1,2,3] => [1,2,3] => [3,2,1] => 0
[2,1,2] => [2,1,3] => [2,1,3] => [3,1,2] => 1
[2,2,1] => [3,1,2] => [2,3,1] => [1,3,2] => 1
[1,2,3] => [1,2,3] => [1,2,3] => [3,2,1] => 0
[1,3,2] => [1,3,2] => [3,1,2] => [2,1,3] => 1
[2,1,3] => [2,1,3] => [2,1,3] => [3,1,2] => 1
[2,3,1] => [3,1,2] => [2,3,1] => [1,3,2] => 1
[3,1,2] => [2,3,1] => [1,3,2] => [2,3,1] => 1
[3,2,1] => [3,2,1] => [3,2,1] => [1,2,3] => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => [3,2,1,4] => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => [3,4,2,1] => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => [3,2,1,4] => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => [3,4,2,1] => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => [3,2,1,4] => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => [3,4,2,1] => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => [4,2,1,3] => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => [2,1,4,3] => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => [4,2,3,1] => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => [2,4,3,1] => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => [2,4,1,3] => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => [4,3,2,1] => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => [3,2,1,4] => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => [4,2,1,3] => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => [2,1,4,3] => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => [2,1,3,4] => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => [4,2,3,1] => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => [2,4,3,1] => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => [2,4,1,3] => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => [3,4,2,1] => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => [2,3,1,4] => 2
Description
The number of ascents of a permutation.
Matching statistic: St000703
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00086: Permutations first fundamental transformationPermutations
St000703: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => [1] => 0
[1,1] => [1,2] => [1,2] => [1,2] => 0
[1,2] => [1,2] => [1,2] => [1,2] => 0
[2,1] => [2,1] => [2,1] => [2,1] => 1
[1,1,1] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,1,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,2,1] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[2,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,1,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,1] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[3,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,2,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[2,1,2] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,2,1] => [3,1,2] => [2,3,1] => [3,2,1] => 1
[1,2,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,2] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[2,1,3] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,3,1] => [3,1,2] => [2,3,1] => [3,2,1] => 1
[3,1,2] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[3,2,1] => [3,2,1] => [3,2,1] => [3,1,2] => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => [3,2,4,1] => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => [3,2,4,1] => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => [3,2,4,1] => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => [2,3,1,4] => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => [2,4,3,1] => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => [1,4,3,2] => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => [3,4,1,2] => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => [2,3,1,4] => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => [2,4,3,1] => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => [3,2,4,1] => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => [2,4,1,3] => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => [1,4,3,2] => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => [3,4,1,2] => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => [3,4,2,1] => 2
Description
The number of deficiencies of a permutation. This is defined as dec(σ)=#{i:σ(i)<i}. The number of exceedances is [[St000155]].
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00131: Permutations descent bottomsBinary words
St000288: Binary words ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => => ? = 0
[1,1] => [1,2] => [1,2] => 0 => 0
[1,2] => [1,2] => [1,2] => 0 => 0
[2,1] => [2,1] => [2,1] => 1 => 1
[1,1,1] => [1,2,3] => [1,2,3] => 00 => 0
[1,1,2] => [1,2,3] => [1,2,3] => 00 => 0
[1,2,1] => [1,3,2] => [3,1,2] => 10 => 1
[2,1,1] => [2,3,1] => [1,3,2] => 01 => 1
[1,1,3] => [1,2,3] => [1,2,3] => 00 => 0
[1,3,1] => [1,3,2] => [3,1,2] => 10 => 1
[3,1,1] => [2,3,1] => [1,3,2] => 01 => 1
[1,2,2] => [1,2,3] => [1,2,3] => 00 => 0
[2,1,2] => [2,1,3] => [2,1,3] => 10 => 1
[2,2,1] => [3,1,2] => [2,3,1] => 10 => 1
[1,2,3] => [1,2,3] => [1,2,3] => 00 => 0
[1,3,2] => [1,3,2] => [3,1,2] => 10 => 1
[2,1,3] => [2,1,3] => [2,1,3] => 10 => 1
[2,3,1] => [3,1,2] => [2,3,1] => 10 => 1
[3,1,2] => [2,3,1] => [1,3,2] => 01 => 1
[3,2,1] => [3,2,1] => [3,2,1] => 11 => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => 100 => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => 100 => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => 001 => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => 100 => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => 100 => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => 001 => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => 100 => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => 100 => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => 001 => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => 100 => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => 100 => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => 010 => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => 010 => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => 110 => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => 000 => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => 100 => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => 100 => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => 100 => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => 100 => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => 101 => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => 010 => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => 010 => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => 110 => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => 001 => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => 110 => 2
[3,2,1,1] => [3,4,2,1] => [1,4,3,2] => 011 => 2
Description
The number of ones in a binary word. This is also known as the Hamming weight of the word.
Matching statistic: St000354
Mp00055: Parking functions to labelling permutationPermutations
Mp00062: Permutations Lehmer-code to major-code bijectionPermutations
Mp00066: Permutations inversePermutations
St000354: Permutations ⟶ ℤResult quality: 100% values known / values provided: 100%distinct values known / distinct values provided: 100%
Values
[1] => [1] => [1] => [1] => ? = 0
[1,1] => [1,2] => [1,2] => [1,2] => 0
[1,2] => [1,2] => [1,2] => [1,2] => 0
[2,1] => [2,1] => [2,1] => [2,1] => 1
[1,1,1] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,1,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,2,1] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[2,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,1,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,1] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[3,1,1] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[1,2,2] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[2,1,2] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,2,1] => [3,1,2] => [2,3,1] => [3,1,2] => 1
[1,2,3] => [1,2,3] => [1,2,3] => [1,2,3] => 0
[1,3,2] => [1,3,2] => [3,1,2] => [2,3,1] => 1
[2,1,3] => [2,1,3] => [2,1,3] => [2,1,3] => 1
[2,3,1] => [3,1,2] => [2,3,1] => [3,1,2] => 1
[3,1,2] => [2,3,1] => [1,3,2] => [1,3,2] => 1
[3,2,1] => [3,2,1] => [3,2,1] => [3,2,1] => 2
[1,1,1,1] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,1,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,2,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,2,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[2,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,3,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[3,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,1,4] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,4,1] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,4,1,1] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[4,1,1,1] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[1,1,2,2] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,2,1,2] => [1,3,2,4] => [3,1,2,4] => [2,3,1,4] => 1
[1,2,2,1] => [1,4,2,3] => [3,4,1,2] => [3,4,1,2] => 1
[2,1,1,2] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,2,1] => [2,4,1,3] => [1,3,4,2] => [1,4,2,3] => 1
[2,2,1,1] => [3,4,1,2] => [3,1,4,2] => [2,4,1,3] => 2
[1,1,2,3] => [1,2,3,4] => [1,2,3,4] => [1,2,3,4] => 0
[1,1,3,2] => [1,2,4,3] => [4,1,2,3] => [2,3,4,1] => 1
[1,2,1,3] => [1,3,2,4] => [3,1,2,4] => [2,3,1,4] => 1
[1,2,3,1] => [1,4,2,3] => [3,4,1,2] => [3,4,1,2] => 1
[1,3,1,2] => [1,3,4,2] => [2,4,1,3] => [3,1,4,2] => 1
[1,3,2,1] => [1,4,3,2] => [4,3,1,2] => [3,4,2,1] => 2
[2,1,1,3] => [2,3,1,4] => [1,3,2,4] => [1,3,2,4] => 1
[2,1,3,1] => [2,4,1,3] => [1,3,4,2] => [1,4,2,3] => 1
[2,3,1,1] => [3,4,1,2] => [3,1,4,2] => [2,4,1,3] => 2
[3,1,1,2] => [2,3,4,1] => [1,2,4,3] => [1,2,4,3] => 1
[3,1,2,1] => [2,4,3,1] => [4,1,3,2] => [2,4,3,1] => 2
[3,2,1,1] => [3,4,2,1] => [1,4,3,2] => [1,4,3,2] => 2
Description
The number of recoils of a permutation. A '''recoil''', or '''inverse descent''' of a permutation π is a value i such that i+1 appears to the left of i in π1,π2,,πn. In other words, this is the number of descents of the inverse permutation. It can be also be described as the number of occurrences of the mesh pattern ([2,1],(0,1),(1,1),(2,1)), i.e., the middle row is shaded.
The following 5 statistics, ordered by result quality, also match your data. Click on any of them to see the details.
St001427The number of descents of a signed permutation. St001624The breadth of a lattice. St000761The number of ascents in an integer composition. St001330The hat guessing number of a graph. St001946The number of descents in a parking function.