Chapter 2, Problem 13E

Find the Banzhaf power distribution of a weighted voting system with four players in which the winning coalitions (with critical players underlined) are

$\left\{{\underset{\_}{P}}_1,{\underset{\_}{P}}_2,{\underset{\_}{P}}_3\right\}$, $\left\{{\underset{\_}{P}}_1,{\underset{\_}{P}}_2,{\underset{\_}{P}}_4\right\}$, $\left\{{\underset{\_}{P}}_1,{\underset{\_}{P}}_2,{\underset{\_}{P}}_3,{\underset{\_}{P}}_4\right\}$.