// / x\ \
// x |x| \ || x*|-1 - -| |
|| ---------- for --- < 1| || \ 2/ |x| |
|| 2 2 | || ----------- for --- < 1|
|| / x\ | || 3 2 |
|| 2*|1 - -| | || / x\ |
|| \ 2/ | || 2*|-1 + -| |
|| | || \ 2/ |
|< oo | + |< |
|| ___ | || oo |
|| \ ` | || ___ |
|| \ -n n | || \ ` |
|| / n*2 *x otherwise | || \ -n 2 n |
|| /__, | || / 2 *n *x otherwise |
||n = 1 | || /__, |
\\ / ||n = 1 |
\\ /
$$\begin{cases} \frac{x}{2 \left(1 - \frac{x}{2}\right)^{2}} & \text{for}\: \frac{\left|{x}\right|}{2} < 1 \\\sum_{n=1}^{\infty} 2^{- n} n x^{n} & \text{otherwise} \end{cases} + \begin{cases} \frac{x \left(- \frac{x}{2} - 1\right)}{2 \left(\frac{x}{2} - 1\right)^{3}} & \text{for}\: \frac{\left|{x}\right|}{2} < 1 \\\sum_{n=1}^{\infty} 2^{- n} n^{2} x^{n} & \text{otherwise} \end{cases}$$
Piecewise((x/(2*(1 - x/2)^2), |x|/2 < 1), (Sum(n*2^(-n)*x^n, (n, 1, oo)), True)) + Piecewise((x*(-1 - x/2)/(2*(-1 + x/2)^3), |x|/2 < 1), (Sum(2^(-n)*n^2*x^n, (n, 1, oo)), True))