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-1 votes
1 answer
83 views

How many ways can someone choose a permutation $w $ and color each one of the integers [n] so that the minimum element of every cycle of w is white?

In how many ways can someone choose a permutation $w \in S_n$ and color each one of the integers $1,2,\ldots,n$ white, yellow or blue so that the minimum element of every cycle of $w$ is white? ...
user avatar
1 vote
1 answer
74 views

What is the Lie theoretic interpretation of conjugate of a partition?

For a partition $\lambda$ it is very well-known operation to take its conjugate partition $\lambda'$ which is obtained by transposing the Young diagram of $\lambda$. A partition $\lambda$ can be ...
ArB's user avatar
  • 237
0 votes
0 answers
69 views

Counting covered pairs of integer partitions

I am trying to solve a problem in algebric combinatorics, where i want to prove that for integers $m,n$ and pairs ($\lambda$ , $\mu$) of integer partitions with a maximum of $m$ non zero parts which ...
Truru's user avatar
  • 1
2 votes
2 answers
303 views

Proof of an identity about integer partition

I'd like to know how to prove the following identity, $$\sum_{k=1}^n k\, p(n, k) = \sum_{r,s\ge 1, rs\le n} p(n-rs)$$ where $n\in N^+$. Here, $p(n)$ counts the number of possible partitions of $n$. ...
Edward's user avatar
  • 93
9 votes
1 answer
746 views

Young projectors in Fulton and Harris

In Section 4 of Fulton and Harris' book Representation Theory, they give the definition of a Young tableau of shape $\lambda = (\lambda_1,\dots,\lambda_k)$ and then define two subgroups of $S_d$, the ...
Alex Ortiz's user avatar
  • 25.2k
2 votes
1 answer
98 views

Counting solutions to equations involving partitions

This is a problem that has come up in my research and seems to be true from numerical tests via Mathematica. It should be provable in general, but I have been unable to show it so far. It would be ...
Alec Barns-Graham's user avatar
1 vote
1 answer
97 views

Is there any proof of this identity?

$$\prod\limits_{i=1}^{\infty}\frac{1}{1-yx^{i}}=\sum\limits_{k=0}^{\infty}\frac{y^k x^k}{(1-x)(1-x^2)...(1-x^k)}$$ I know its combinatorial proof through "inspection",but is it true when $x,y$ are ...
user510013's user avatar
9 votes
0 answers
183 views

Inequality for hook numbers in Young diagrams

Consider a Young diagram $\lambda = (\lambda_1,\ldots,\lambda_\ell)$. For a square $(i,j) \in \lambda$ define hook numbers $h_{ij} = \lambda_i + \lambda_j' -i - j +1$ and complementary hook numbers $...
Igor Pak's user avatar
  • 1,366
2 votes
0 answers
533 views

Proving Identities using Partition and Generating Function

I have a problem with these two questions: Let $P_E(n)$ be the number of partitions of $n$ with an even number of parts, $P_O(n)$ the number of partitions of n with an odd number of parts, and $...
Taxxi's user avatar
  • 1,502
15 votes
2 answers
4k views

Identity involving partitions of even and odd parts.

First, denote by $p_E(n)$ be the number of partitions of $n$ with an even number of parts, and let $p_O(n)$ be those with an odd number of parts. Moreover, let $p_{DO}(x)$ be the number of partitions ...
seungyeon's user avatar
  • 153