large numbers as counterexamples
5574
Conjectures that have been disproved with extremely large counterexamples?
77735
When $\Bbb Z_n$ is a domain. Counterexample to $ab \equiv 0 \Rightarrow a\equiv 0$ or $b\equiv 0\pmod n$
104773
Generalized PNT in limit as numbers get large
106291
Central limit theorem and the law of large numbers
80019
$\varepsilon$-number countability without choice
134440
An unexpected application of non-trivial combinatorics
25874
Showing that a certain map is not flat by explicit counterexample
10905
Avoiding negative integers in proof of Fundamental Theorem of Arithmetic
51129
Proving $n^\epsilon > \log(n)$ for sufficiently large $n$
65759
A possible incorrect application of Law of Large numbers
47697
Russell's paradox: a set cannot contain its own powerset
131385
How to provide a counterexample for if $n$ is prime, then $2^n -1$ is prime
129693
An interesting problem with "decomposing" natural numbers.
148260
Polylogarithms of negative integer order
35371
The pseudoness of pseudorandom number generators
79974
The cardinality of Lebesgue sets
50235
Numbering theorem-like environments