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Tagged with ho.history-overview expanders
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Papers to credit for spectral partitioning of graphs
If $G=(V,E)$ is an undirected $d$-regular graph and $S$ is a subset of the vertices of cardinality $\leq |V|/2$, call the edge expansion of $S$ the quantity
$\phi(S) := \frac {Edges(S,V-S)}{d\cdot |S|...
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27
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2
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Why are Ramanujan graphs named after Ramanujan?
I recently taught expanders, and introduced the notion of Ramanujan graphs.
Michael Forbes asked why they are called this way, and I had to admit I don't know.
Anyone?
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