Exercise · ZW-CANTOR-S-DIAGONAL-THEOREM-005 · ★★☆ Intermediate
With \(s_1=000\ldots\), \(s_2=111\ldots\) and \(s_3=0101\ldots\), what are the first three terms of the diagonal sequence \(t\), where \(t(n)=1-s_n(n)\)?
Choose one option.
A \(0,0,0\) B \(1,1,1\) C \(0,1,0\) D \(1,0,1\)
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Explanation \(t(1)=1-s_1(1)=1\), \(t(2)=1-s_2(2)=0\) and \(t(3)=1-s_3(3)=1\). The other sequences do not flip each diagonal term.
Theorem proving that the set \(\{0,1\}^{\mathbb{N}}\) of binary sequences is not countable, by building a sequence that appears in no list.
\[t(n)=1-s_n(n)\]
More practice problems: cantor's diagonal theorem