Yet another convergence problem

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Homework Statement


It's the sum (n=1 to infinity) of (n!)/(2^(n^2)) I hope that's not too hard to read?


Homework Equations


The ratio test, I think? Since it contains a factorial.


The Attempt at a Solution


It seems like I'm never short of calculus questions. Everytime I try to apply the ratio test, I end up getting to (n+1)(2^(n^2)) / (2^(n+1)^2) and I'm unsure of where to go from there to see if it converges or not.
 
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Try expanding 2^(n+1)^2 and then rewrite that using some rules of exponents.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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