Are there any mathematical discoveries that are considered trivial or useless?
91834
Useless math that became useful
147924
Math problems that are impossible to solve
51278
Theorems with an extraordinary exception or a small number of sporadic exceptions
79131
List of generally believed conjectures which cannot all be true
22391
Is the set of all pairs of real numbers uncountable?
113606
Dimensionless quantities
49766
Examples of results failing in higher dimensions
2341
An expression that adds little information
48879
Why do mathematicians use single-letter variables?
41262
Does the concept of infinity have any practical applications?
38820
Negating the Legendre's conjecture
49298
What are some examples of induction where the base case is difficult but the inductive step is trivial?
10905
Avoiding negative integers in proof of Fundamental Theorem of Arithmetic
56599
Is $R^2$ useful or dangerous?
3663
Finding counterexamples in elementary set theory.
2800
Is it possible to prove a null hypothesis?
76434
What is the measure of the set of numbers in $[0,1]$ whose decimal expansions do not contain $5$?