Questions tagged [multiset]

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Partitions of a multiset into equal parts

I am interested in a possible generalization of the following fact from combinatorics: If $n<m$ then there are at least as many ways to partition a set of size $nm$ into $m$ sets each of size $n$ ...
Nate's user avatar
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3D generalization of Gaussian q-binomial coefficient

It is known that the coefficient of $q^t$ in Gaussian binomial coefficient $\binom{m+n}m_q$ equals the number of permutations of the multiset $\{0^m, 1^n\}$ with $t$ inversions. Is there a closed ...
Max Alekseyev's user avatar
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Does there exist a canonical form for normal matrices which extends the following embedding?

Given an unordered pair of complex numbers $\{w,z\}$, we can associate to it the complex matrix $$\frac 1 2\left[\begin{matrix}w + z + \frac{\left(w - z\right)^{2} + \left|{w - z}\right|^{2}}{2 \left|{...
wlad's user avatar
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A natural sum over multisets (expectation over multinomial)

I think this is a natural question but am not sure where to find resources. Consider the possible multisets arising from choosing $n$ times an item from one of $k$ categories. We can represent one ...
usul's user avatar
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An equation involving multisets

For finite multisets $A, B, C, A', B', C'$, if $A \uplus B \uplus \{B \uplus C\} \uplus \{A \uplus \{C\}\}$ = $A' \uplus B' \uplus \{B' \uplus C'\} \uplus \{A' \uplus \{C'\}\}$, must $A=A',B=B',C=C'$, ...
Jeremy's user avatar
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