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1d
comment Calculate $1^1 + 2^2 + 3^3 + … + n^n$
I am not aware of any such formula, but you can find an asymptotic expansion as $n\to +\infty$.
1d
comment Is $z/\sin z$ analytic in the complex plane?
@user202534: $0$ is a removable singularity (see why?), but $\sin(z)$ has other zeros than $0$...
1d
awarded  Constituent
Dec
16
reviewed Leave Open How to prove this number is not rational?
Dec
16
comment Show that $E(X|Y, Z) = E(X|Y)$ almost surely with condition Z is independent of $(X, Y)$
You mean $H(Y,Z)$ and $h(Y)$, don't you?
Dec
15
reviewed Reviewed Fixed Spaces for Group Elements
Dec
15
reviewed Close Investigate convergence of a series
Dec
15
reviewed Close orthogonal and special orthogonal group of dimension $2$, group of isometries of $S_1$, $\mathbb{R}^2$
Dec
15
reviewed Leave Open Proof that the kernel of an endomorphism to the power $n$ is a subset of the kernel of the endomorphism to the power $n+1$
Dec
15
reviewed Close Prove: if a series converges absolutely (assuming the series is not equal to 0) then $1/|a_k$| diverges
Dec
15
reviewed Close Find conditions on $m$ and $n$ that ensure that $f$ is a bijection.
Dec
15
reviewed Close PDF of Gamma R.V.
Dec
15
reviewed Close Double angle sine
Dec
15
revised Infinite sum for a geometric series.
corrected tags
Dec
14
comment Convergence of a certain series of Primes
@happymath: Yes. You can check this with the Integral Test for convergence. Actually, the series converges iff $\delta > 1$.
Dec
14
comment Convergence of a certain series of Primes
@happymath. Yes, it's enough here.
Dec
14
comment Limit law of real-valued independent random variables
Beware! You could apply the lemma if you had convergence in distribution for the pair $(X_n,Y_n)$ to $(X,Y)$.
Dec
14
comment Convergence of a certain series of Primes
@happymath: Good question! In this case there is no such problem since, if $u_n \sim v_n$ with $v_n \to +\infty$, then $\log(u_n) \sim \log(v_n)$. Proof: $\log(u_n) = \log (v_n) + \log(\frac{u_n}{v_n})$ and $\log \frac{u_n}{v_n} \to 0$.
Dec
14
answered Convergence of a certain series of Primes
Dec
10
awarded  Nice Answer