One Represented With Infinite Twos

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Theorem

\(\ds 1\) \(=\) \(\ds \cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } + \cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } + \cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } + \cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } + \cfrac 2 {\cfrac 2 {\ddots + \ddots} + \cfrac 2 {\ddots + \ddots} } } } }\)

where the bottom row contains $2^n$ ones and the pyramid above it contains $\paren{2^n - 1}$ twos.


Proof

We have:

\(\ds 1\) \(=\) \(\ds \cfrac 2 {1 + 1}\) One Layer Deep: $2^1$ ones and $\paren{2^1 - 1}$ twos
\(\ds \) \(=\) \(\ds \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} }\) Two Layers Deep: $2^2$ ones and $\paren{2^2 - 1}$ twos
\(\ds \) \(=\) \(\ds \cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } }\) Three Layers Deep: $2^3$ ones and $\paren{2^3 - 1}$ twos
\(\ds \) \(=\) \(\ds \cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } }\) Four Layers Deep: $2^4$ ones and $\paren{2^4 - 1}$ twos
\(\ds \) \(=\) \(\ds \cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } + \cfrac 2 {\cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } + \cfrac 2 {\cfrac 2 {1 + 1} + \cfrac 2 {1 + 1} } } } }\) Five Layers Deep: $2^5$ ones and $\paren{2^5 - 1}$ twos
\(\ds \) \(=\) \(\ds \cdots\)

$\blacksquare$