ThmDex – An index of mathematical definitions, results, and conjectures.
Result R4216 on D76: Set intersection
Finite set intersection is invariant under bijective shifting of indices
Formulation 0
Let $X_1, \ldots, X_N$ each be a D11: Set.
Let $\pi : \{ 1, \ldots, N \} \to \{ 1, \ldots, N \}$ be a D353: Set automorphism.
Then \begin{equation} \bigcap_{n = 1}^N X_n = \bigcap_{n = 1}^N X_{\pi(n)} \end{equation}
Formulation 1
Let $X_1, \ldots, X_N$ each be a D11: Set.
Let $\pi : \{ 1, \ldots, N \} \to \{ 1, \ldots, N \}$ be a D353: Set automorphism.
Then \begin{equation} X_1 \cap X_2 \cap \cdots \cap X_N = X_{\pi(1)} \cap X_{\pi(2)} \cap \cdots \cap X_{\pi(N)} \end{equation}
Proofs
Proof 0
Let $X_1, \ldots, X_N$ each be a D11: Set.
Let $\pi : \{ 1, \ldots, N \} \to \{ 1, \ldots, N \}$ be a D353: Set automorphism.