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Tagged with algebraic-combinatorics catalan-numbers
2 questions
14
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1
answer
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Reference request: Heyting algebra structure on Catalan numbers
I've noticed that for every natural number $n\in\mathbb{N}$, there is a finite Heyting algebra with cardinality $C(n)$, where $C(n)$ is the $n$th Catalan number,
$$1,1,2,5,14,42,132,\ldots$$
I'm ...
3
votes
1
answer
308
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Semi-planar partition monoid/algebra
Here are some beginner questions on partition algebras...
I am trying to understand the monoid called $P_k$ in Tom Halverson, Arun Ram, Partition Algebras. For the sake of simplicity, let $k$ be a ...