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 89 What's so special about standard deviation? 63 How many “super imaginary” numbers are there? 47 An integral for the New Year 2016 45 How to attack “if true, prove it; if not true, give a counterexample” question? 44 Calculating the square root of 2

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 +15 I tried to prove $\sum_{n=0}^∞ \frac{n^2}{2^n} = 6$ but I feel that my proof is long. Can anyone provide an alternate proof? +10 So how exactly is the Einstein lower and upper index convention? +10 Is $\infty^\infty$ indeterminate? +10 Integral of a radial symmetric function.

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 9 Do the octonions contain infinitely many copies of the quaternions? 4 Calculation in Routh's theorem 4 What's the name for this numerical integration algorithm? 3 Morrie's law with sines 3 When can limits be moved to coefficients in power series?

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 11 prove $\int_0^\infty \frac{\log^2(x)}{x^2+1}\mathrm dx=\frac{\pi^3}{8}$ with real methods 3 Following Fibonacci 1 Studying quantized algebras, why introduce $q^{1/2}$ instead of just $q$? 1 Generative Adversarial Networks - discriminator function “running away” 0 Evaluate $\lim_{n \rightarrow \infty } \int_0^{\pi/2} \sqrt{n \sin{\frac{x}{n}} }dx$

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