Изменения

<math> | A | = | A_n| + \Bigg( \sum_{I \subset \{ 1,2, \ldots ,n-1 \} } (-1)^{|I|+1} \Big| \bigcap_{ j \in I } A_j \Big| \Bigg) - \Bigg( \sum_{I \subset \{ 1,2, \ldots ,n-1 \} } (-1)^{|I|+1} \Big| \bigcap_{ j\in I \cup \{ n \} } A_j \Big| \Bigg) = \sum_{I \subset \{ 1,2, \ldots ,n \} } (-1)^{k|I|+1} \Big| \bigcap_{ j \in I } A_j \Big| </math>