The sum of the first n inverse square roots is less than square root of $n$
17157
Proving $\sum\limits_{k=1}^{n}{\frac{1}{\sqrt{k}}\ge\sqrt{n}}$ with induction
115236
Calculate the sum of inverse values of ${n\choose 0}, {n\choose 1}, ... {n\choose n}$
129351
Show that $\sqrt{n^2+1}-n$ converges to 0
40952
Showing that sum of angles of hyperbolic triangle is strictly less than $\pi$
58264
How to derive the formula for the sum of the first $n$ perfect squares?
40784
$\sum_{k=m}^{n}(-1)^k\binom{n}{k}\binom{k}{m}=0, n>m\geq 0$
93820
Fermat's little theorem applied for $n$'th root existence $\!\bmod p$
140359
Can the sum of finitely many inverses of distinct odd integers $\geq 3$ be 1?
20317
Proving $\sum_{k=1}^{n}{(-1)^{k+1} {{n}\choose{k}}\frac{1}{k}=H_n}$
77554
Inverse of the sum of matrices
43188
The $n^{th}$ root of the geometric mean of binomial coefficients.
67291
Prove that there exists $n\in\mathbb{N}$ such that $f^{(n)}$ has at least n+1 zeros on $(-1,1)$
22129
Why is $\sqrt{\sum_{i=1}^n |v_i|^2} \leq \sum_{i=1}^n |v_i|$ true?
31766
Prove that $a_{n}=0$ for all $n$, if $\sum a_{kn}=0$ for all $k\geq 1$
107765
Prove that there exists two roots in $[-1,1]$
120093
Proof of inequality $2(\sqrt{n+1}-\sqrt{n}) < \frac{1}{\sqrt{n}} < 2(\sqrt{n} - \sqrt{n-1})$ using induction
5043
Show that $2^n>1+n\sqrt{2^{n-1}}$