Fix typos in bw(S,T) sum condition and argument#49
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In the general definition of bw(S,T), the sum is written over u \in S, v \not\in S, which makes the parameter T completely unused in the formula body. It should be v \in T to match the signature bw(S,T). The special case where T = V\S (used for bisection bandwidth) makes v \in T equivalent to v \not\in S, which is likely the source of the confusion. Also as a minor note: w(u,v) in the sum refers to the bandwidth (weight) of a single edge, while w(S,T) defined just above refers to the width (cardinality of edges between them), yet both use the same letter w. A different notation for one of them (e.g. bw(u,v) for the edge weight as defined right above) might avoid confusion.
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In the general definition of bw(S,T), the sum is written over u \in S, v \not\in S, which makes the parameter T completely unused in the formula body. It should be v \in T to match the signature bw(S,T). The special case where T = V\S (used for bisection bandwidth) makes v \in T equivalent to v \not\in S, which is likely the source of the confusion.
Another potential problem is that w(u,v) in the sum of bw(S,T) refers to the bandwidth (weight) of a single edge, while w(S,T) defined just above refers to the width (cardinality of edges between them), yet both use the same letter w. A different notation for the argument of the sum, such as bw(u,v) for the edge weight as defined right above for this purpose, might avoid confusion.