coefficient of [x^ny^m], 1 \leq m \leq n; \newline \\ \frac{1}{(1-xy)^2(1-x)}\log(1/(1-xy)) \newline \\ =\frac{1}{(1-xy)(1-x)}[\frac{1}{1-xy}\log(1/(1-xy))] \newline = \sum_{p>0} H_p (xy)^p * \sum_{q>0} (xy)^q *\sum_{r>0} x^r \newline \\ Note:\; p+q+r = n, p+q = m \\ =\sum_{p+q =m} \sum_{k=0}^{m} H_k (xy)^{p+q} * \sum_{r>0}x^r \\ =\sum_{p+q =m}((m+1)(H_{m+1}-1)) (xy)^{p+q} *\sum_{r>0}x^r \\ => [x^ny^m] = (m+1)(H_{m+1}-1) \\ but \;the \;answer\; does \;not\; match\; with\; the\; book's \;answer?\; The \;correct\; answer\; is\; \\ (m+1)H_m - 1. \\ what \;does\; go \;wrong \;here?