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Let $p$ and $q$ be partitions of $n$. We say $q$ refines $p$ if the parts of $p$ can be subdivided to produce the parts of $q$. For example, $(5,5,1)$ refines $(6,5)$ but not $(7,4)$. $(n)$ refines only itself, and $(1,...,1)$ refines all partitions of $n$.

For each partition of $n$, count the number of partitions refining it. Let $F(n)$ be the sum of these counts. For example, $F(3) = 3+2+1=6$, and $F(4) = 5+3+3+2+1=14$. What is known about the asymptotics of $F(n)$?

My motivation is from looking at multinomials.

Note: Refinement is not the dominance order. It is related to the refinement of set partitions.

EDIT: I found why I was looking at these numbers:

JonMarkPerryBlog:WordPress

Let $p$ and $q$ be partitions of $n$. We say $q$ refines $p$ if the parts of $p$ can be subdivided to produce the parts of $q$. For example, $(5,5,1)$ refines $(6,5)$ but not $(7,4)$. $(n)$ refines only itself, and $(1,...,1)$ refines all partitions of $n$.

For each partition of $n$, count the number of partitions refining it. Let $F(n)$ be the sum of these counts. For example, $F(3) = 3+2+1=6$, and $F(4) = 5+3+3+2+1=14$. What is known about the asymptotics of $F(n)$?

My motivation is from looking at multinomials.

Note: Refinement is not the dominance order. It is related to the refinement of set partitions.

Let $p$ and $q$ be partitions of $n$. We say $q$ refines $p$ if the parts of $p$ can be subdivided to produce the parts of $q$. For example, $(5,5,1)$ refines $(6,5)$ but not $(7,4)$. $(n)$ refines only itself, and $(1,...,1)$ refines all partitions of $n$.

For each partition of $n$, count the number of partitions refining it. Let $F(n)$ be the sum of these counts. For example, $F(3) = 3+2+1=6$, and $F(4) = 5+3+3+2+1=14$. What is known about the asymptotics of $F(n)$?

My motivation is from looking at multinomials.

Note: Refinement is not the dominance order. It is related to the refinement of set partitions.

EDIT: I found why I was looking at these numbers:

JonMarkPerryBlog:WordPress

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user9072
user9072
Rewrote question to use the correct term "refinement" instead of "dominance."
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Douglas Zare
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Dominated Partition Numbers Counting refinements of partitions

A partition ofLet $p$ ofand $n$ consists$q$ be partitions of a sum to $n$. We say $p$ dominates $q$ refines $p$ if the summands inparts of $p$ are constructable by those incan be subdivided to produce the parts of $q$. So, forFor example, $(6,5)$ dominates $(5,5,1)$ refines $(6,5)$ but not $(7,4)$. $(n)$ dominates everythingrefines only itself, and $(1,...,1)$ dominates nothingrefines all partitions of $n$.

We now add up allFor each partition of $n$, count the number of partitions and their dominatoriesrefining it. Let $F(n)$ be the sum of these counts. For example, $F(3) = 3+2+1=6$, and call this function $F$$F(4) = 5+3+3+2+1=14$. Are thereWhat is known about the asymptotics onof $F$$F(n)$?

MotivationMy motivation is from looking at multinomials.

ThisNote: Refinement is not the same definition of dominance order. given at Wikipedia, which has $42$ dominatingIt is related to the $33$ for examplerefinement of set partitions.

Dominated Partition Numbers

A partition of $p$ of $n$ consists of a sum to $n$. We say $p$ dominates $q$ if the summands in $p$ are constructable by those in $q$. So, for example, $(6,5)$ dominates $(5,5,1)$ but not $(7,4)$. $(n)$ dominates everything, $(1,...,1)$ dominates nothing.

We now add up all partitions and their dominatories, and call this function $F$. Are there known asymptotics on $F$?

Motivation is from looking at multinomials.

This is not the same definition of dominance given at Wikipedia, which has $42$ dominating $33$ for example.

Counting refinements of partitions

Let $p$ and $q$ be partitions of $n$. We say $q$ refines $p$ if the parts of $p$ can be subdivided to produce the parts of $q$. For example, $(5,5,1)$ refines $(6,5)$ but not $(7,4)$. $(n)$ refines only itself, and $(1,...,1)$ refines all partitions of $n$.

For each partition of $n$, count the number of partitions refining it. Let $F(n)$ be the sum of these counts. For example, $F(3) = 3+2+1=6$, and $F(4) = 5+3+3+2+1=14$. What is known about the asymptotics of $F(n)$?

My motivation is from looking at multinomials.

Note: Refinement is not the dominance order. It is related to the refinement of set partitions.

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