What's the value of this Vieta-style product involving the golden ratio?



One way of looking at the Vieta product
2π=222+222+2+22

is as the infinite product of a series of successive 'approximations' to 2, defined by a0=2, ai+1=2+ai (or more accurately, their ratio to their limit 2). This allows one to see that the product converges; if |ai2|=ϵ, then |ai+12|ϵ/2 and so the terms of the product go as roughly (1+2i).
Now, the sequence of infinite radicals a0=1, ai+1=1+ai converges exponentially to the golden ratio ϕ, and so the same sort of infinite product can be formed:
Φ=1ϕ1+1ϕ1+1+1ϕ
and an equivalent proof of convergence goes through. The question is, what's the value of Φ? The usual proof of Vieta's product by way of the double-angle formula for sin doesn't translate over, and from what I know of the logistic map it seems immensely unlikely that there's any function conjugate to the iteration map here in the same way that the trig functions are suitably conjugate to the version in the Vieta product. Is there any other approach that's likely to work, or is Φ just unlikely to have any formula more explicit than its infinite product?



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