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Fix sign for fees
@@ -208,9 +208,9 @@ The new transaction balance is thus
$$
\begin{array}
- .\sum(\mathrm{Inputs}) - \sum(\mathrm{Outputs}) + \sum(\mathrm{fee}_i.G) \\\\
- \sum\hat{C_i} - \sum\hat{C_j} + \sum(\mathrm{fee}_i.G) \\\\
- \sum(C_i + \mathrm{H}(C_i \Vert s_i).G) - \sum(C_j + \mathrm{H}(C_j \Vert s_j).G) + \sum(\mathrm{fee}.G) \\\\
+ .\sum(\mathrm{Inputs}) - \sum(\mathrm{Outputs}) - \sum(\mathrm{fee}_i.G) \\\\
+ \sum\hat{C_i} - \sum\hat{C_j} - \sum(\mathrm{fee}_i.G) \\\\
+ \sum(C_i + \mathrm{H}(C_i \Vert s_i).G) - \sum(C_j + \mathrm{H}(C_j \Vert s_j).G) - \sum(\mathrm{fee}.G) \\\\
\text{If the accounting is correct, all values will cancel} \\\\
\sum(k_i + \mathrm{H}(C_i \Vert s_i).G) - \sum(k_j + \mathrm{H}(C_j \Vert s_j).G) \\\\
\text{The sum of all the blinding factors (times G) is the definition of the excess,}\\; x_s\cdot G = X_s \\\\
