Pigeonhole principle problem 4
126015
Elementary number theory in sets
143573
Problem (1.8) A Path to Combinatorics Solution Verification.
69748
Semi-Ambiguous Combinatorics Problem
46580
Variation on the Monty Hall Problem
377
Problem involving many squares and several variables.
77286
Proving set theory question
102791
pigeonhole principle: at least 1 match/hr for 75 hrs, at most 125 matches, then exactly 24 matches in some interval
70460
How can I solve the following sequence
104309
Pigeon-Hole Principle Common Sum
150324
Pigeonhole principle: prove that any set of $n+1$ integers from $\{1,2,...,2n\}$ has two consecutive integers differ by one.
141379
All groups where underlying set has at most 4 elements
46999
How many fixed points in a permutation
11296
The Monty Hall problem
34334
Combinatorics Problem with symbols and spaces
139039
Stars and Bars Combinatorics Problem
101804
Problem concerning the use of Pigeonhole (Box) principle
52572
Questions relating to inclusion-exclusion principle