Infinite Factorial Sum

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Evaluate- $$\lim_{n\to\infty}\sum_{r=1}^{n}\frac{1}{r!^{2}}$$. Is it possible to find the sum?Tried bringing it to integral form, using concepts of power series known to me, simplifying sum, but could not simplify. Will Stirling's Approximation be of use?

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Nothing is impossible, just believe on computational intelligence

$$\sum_{r=1}^\infty \frac{1}{(r!)^2}=I_0(2)-1\approx1.27959...$$here $I_n(z)$ is the Modified Bessel Function of the First Kind. More information can be found here.