Extending the Basel problem for 1/n^4
15477
Nice proofs of $\zeta(4) = \frac{\pi^4}{90}$?
123495
Find the asymptotic tight bound for $T(n) = 4T(n/2) + n^{2}\log n$
27448
The Collatz conjecture algorithm applied to negative integers
121575
Meet-in-the-middle with checking complexity
108321
On the problem $1$ of Putnam $2009$
99677
Generalization of Cayley-Hamilton
140910
Solving minimization problem $L_2$ IRLS (Iteration derivation)
131559
Lower Bound of Central Binomial Coefficients
111057
On the position of multiple sub and superindices
141010
Computing $n$-th external power of standard simplectic form
92763
Optimising $x_1x_2+x_2x_3+\cdots+x_nx_1$ given certain constraints
57644
Lower bounds for ${{2n} \choose {n}}$
134440
An unexpected application of non-trivial combinatorics
118674
Simple upper bound for $\binom{n}{k}$
24036
extended stars-and-bars problem(where the upper limit of the variable is bounded)
63571
The Mississipi counting problem, this time in circle
116153
The Notorious Triangle Problem