Undergrad Continued fractions and nested radicals

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There is a noted isomorphism between continued fractions and nested radicals, specifically illustrated by the equation y = √(x + √(x + √(x + ...))). The derived quadratic equation y² - y - x = 0 leads to the solution y = (1 ± √(1 + 4x))/2, with the positive branch y = (1 + √(1 + 4x))/2 for x > 0 and y > 0. However, there is a concern regarding the initial condition, as substituting x = 0 yields y = 0, which raises questions about the formula's validity at x = 1. The discussion highlights potential issues with the definition and continuity of the formula. Overall, the relationship between continued fractions and nested radicals invites further exploration and clarification.
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TL;DR
Isomorphism between continued fractions and nested radicals.
There appears to be a simple isomorphism between continued fractions and nested radicals.

Does anybody know more about this?
 

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y=\sqrt{x+\sqrt{x+\sqrt{x+...}}}
From your observation
y^2-y-x=0
y=\frac{1}{2}(1 \pm \sqrt{1+4x})
as x>0,y>0
y=\frac{1}{2}(1+\sqrt{1+4x})
But from the first formula, y(x=0) should be zero. How can we get value of y(x=1) from it which does not show us initial value ? I am afraid this formula is not defined well enough.
 
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