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> "Every one of these graphs has a unique chromatic polynomial" This is incorrect. Two different graphs may have the same chromatic polynomial. For example, al
by vlasev 9y ago
> "Every one of these graphs has a unique chromatic polynomial"
This is incorrect. Two different graphs may have the same chromatic polynomial. For example, all trees of N vertices have the same chromatic polynomial: x(x-1)^(N-1)
- soVeryTired 9y agoI think they're trying to say that the graph uniquely determines the polynomial, rather than that the polynomial determines the graph. Or at least, that's how I read it. But I agree it's a bit ambiguous.
- JadeNB 9y ago> > "Every one of these graphs has a unique chromatic polynomial" > This is incorrect. Two different graphs may have the same chromatic polynomial. For example, all trees of N vertices have the same chromatic polynomial: x(x-1)^(N-1) As soverytired (https://news.ycombinator.com/item?id=14697626 https://news.ycombinator.com/item?id=14697626) points out, you're refuting the claim that the graphs have distinct chromatic polynomials. To say that a graph has a unique chromatic polynomial means that it has only one, not that no other graph has the same one. (For example, (almost?) everyone has a unique biological mother.)