Problem of the Week!
35368
Is it possible to play the Tower of Hanoi with fewer than $2^n-1$ moves?
79881
The Matching Problem/Derangements - n letters to n people
53217
Multi-page equations -- problem
104537
Question Tag problem!
60647
Consecutive days problem #97?
123394
A problem from Isaacs' FGT
124488
Spivak Chapter 2, problems 27 (and 28)
127311
Challenging probability problem
110297
Problem related to quadratic equations
85832
Tough contest problem
14263
Ordering problem
147924
Math problems that are impossible to solve
91509
Buffon needle problem , scenario $\ell>d$
14588
What's wrong with this?
63220
What is the XY problem?
41205
Help me solve a combinatorial problem
76630
"An (obvious) problem" or "a (obvious) problem"?