Pigeon Hole Principle Cases
33998
Show that given seven real numbers, it is always possible take two of them, such that $\left\vert\frac{a-b}{1+ab}\right\vert<\frac{1}{\sqrt{3}}$
107964
Simple combinatorics problem.
105221
Confusion about Satisfiability by a denumerable sequence.
44620
Reference for combinatorial game theory.
126297
A high school Olympiad problem
101804
Problem concerning the use of Pigeonhole (Box) principle
46580
Variation on the Monty Hall Problem
20252
The Axiom of Choice and the Cartesian Product.
78148
Why does the infinite prisoners and hats puzzle require the axiom of choice?
63571
The Mississipi counting problem, this time in circle
68882
Path to Combinatorics Problem [$1.11$]
40439
about a difficult and weird Probability question
143424
Sequence problem involving inequalities
69827
Set conditions at a permutation
69748
Semi-Ambiguous Combinatorics Problem
79341
Question on a probability question
75852
Using Pigeonhole Principle to prove two numbers in a subset of $[2n]$ divide each other