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3 votes
1 answer
82 views

Given a transitive and faithful permutation group $G$, is each set of syntactically transitive permutations connected by another permutation in $G$?

$G$ is a permutation group of degree $n \geq 4$ which acts transitively and faithfully on a set $X$ with $|X| = n$. Given indices $i < j < k \leq n$, elements $\alpha \neq \beta \neq \gamma \in ...
Naiim's user avatar
  • 317
3 votes
0 answers
31 views

Decidability of Wilf Equivalence

I have seen a lot of papers discussing whether various permutation classes are Wilf equivalent to each other. I wonder if we could solve such problems in general with computers. More rigorously, let $\...
abacaba's user avatar
  • 9,080
1 vote
1 answer
192 views

the number of sequences is equal to the number of permutations

Consider the product $A_n = \left\{1\right\} \times \left\{1,2\right\} \times \cdots \times \left\{1,2,\ldots,n\right\}$. For $\sigma = (a_1, a_2, . . . , a_n) \in A_n$, define the set of descents $\...
user avatar
2 votes
0 answers
63 views

When does multiplying by an involution increase the Bruhat Order in the Symmetric Group?

Let $w \in \mathrm{Sym}(n)$ for some positive integer $n$. Let $r$ be an involution in $\mathrm{Sym}(n)$, and write it as the product of disjoint transpositions like so: $$r = \prod_{i=1}^k (a_i,b_i) $...
Rob Nicolaides's user avatar
1 vote
0 answers
297 views

Number for ways to arrange 10 distinct object into 4 distinct boxes

What is the number of ways to arrange 10 distinct objects into 4 distinct boxes, where each box hold no more than 4 objects This question was asked earlier today, but has been deleted, I don't know ...
Aderinsola Joshua's user avatar
1 vote
0 answers
134 views

Permutations That Are Conjugate with an Element From Stabilizer of Another Permutation

We know that permutations, elements of the symmetric group on a finite set with n elements, are conjugate iff they have the same cycle structure. My question is that given two permutations that are ...
selma çetin's user avatar
4 votes
1 answer
104 views

Prove the bijections between the following $(p,q,r)$-shuffles

I am reading the book "From Calculus to Cohomology: De Rham cohomology and characteristic classes" Let $p, q, r$ be nonnegative integers. It says, (for those who own the book, on pg 10) without ...
Damo's user avatar
  • 1,048
3 votes
1 answer
484 views

What is the following way of indexing permutations called?

I'm sure this is well-known but I don't know where to look in order to find it. Consider a permutation, e.g. $\sigma = 2 1 4 3$ in one-line notation. This corresponds to a monotone triangle via \...
Daniel McLaury's user avatar
4 votes
1 answer
8k views

Use of rook polynomials

Use rook polynomials to count the number of permutations of $(1,2,3,4)$ in which $1$ is not in the second position, $2$ is not in the fourth position, and $3$ is not in the first or fourth position. ...
user180588's user avatar